CVE Database - Incorrect Authorization
Browse known vulnerabilities with WAF coverage analysis. See which CVEs are detectable by Web Application Firewalls and their OWASP CRS rules.
CVE-2026-11577
UNKNOWNA flaw was found in Keycloak. A limited administrator can exploit an improper access control vulnerability in the POST /admin/realms/{realm}/partialImport endpoint. This allows them to bypass Fine-Grained Admin Permissions (FGAP) and escalate their privileges to a full realm administrator by importing users with realm-admin role mappings.
CVE-2026-21031
HIGHImproper authorization in AppBlock prior to SMR Jun-2026 Release 1 allows local attacker to launch arbitrary activity. User interaction is required for triggering this vulnerability.
CVE-2026-42547
UNKNOWNIRIS is a web collaborative platform that helps incident responders share technical details during investigations. In versions prior to 2.4.28, users can create alerts for customers that are not assigned to them. This can be abused to falsely attribute fake alerts to customers. In combination with Cross-Site Scripting, this can also be used to exfiltrate alerts from other customers. Version 2.4.28 contains a patch.
CVE-2026-41235
UNKNOWNFroxlor is open source server administration software. Version 2.3.6 lets administrators configure `system.available_shells` as the approved shell list that customers may assign to FTP users. However, the server-side FTP account handlers do not enforce that whitelist when processing add or edit requests. As a result, an authenticated customer with shell delegation enabled can submit an arbitrary shell such as `/bin/bash` even when the panel UI only offers more restricted choices. In deployments that use the default `nssextrausers` integration, the attacker-controlled shell is then propagated into the system account database, leading to real host shell access. Version 2.3.7 fixes the issue.
CVE-2026-50266
UNKNOWNIn OpenStack Neutron before 28.0.1, a project manager can create or update a port on a shared network owned by another project and set device_owner to a value that has "network:" at the beginning ("network:dhcp" for example). The default port RBAC policies incorrectly included PROJECT_MANAGER without requiring network ownership, allowing any project manager to obtain trusted network-service port behavior on shared networks. Depending on backend and deployment, this can bypass anti-spoofing and security group protections, enabling DHCP, MAC, or IP spoofing against other tenants on the shared network. This is a regression of CVE-2015-5240 (OSSA-2015-018).
CVE-2026-10815
MEDIUMA vulnerability was found in LakshayD02 Hostel-Management-System-PHP up to f87e67c283bab6f718faf2fec6ae39a13bd7036b. This issue affects some unknown processing of the file hostel/index.php of the component Admin Dashboard Page. The manipulation of the argument ID results in missing authorization. The attack can be launched remotely. The exploit has been made public and could be used. This product does not use versioning. This is why information about affected and unaffected releases are unavailable. The project was informed of the problem early through an issue report but has not responded yet.
CVE-2026-10860
UNKNOWNA logic error in the MISP CRUD component delete handler allowed validation failures to be bypassed when requests used the HTTP DELETE method. Due to missing parentheses in the delete condition, the expression was evaluated as ($validationError === null && POST) || DELETE, meaning a DELETE request could proceed even when the delete validation callback had rejected the operation. An authenticated attacker with access to an affected delete endpoint could abuse this flaw to delete records that should have been protected by application-level validation or authorization checks.
CVE-2026-41283
UNKNOWNOpenStack Mistral through 22.0.0 allows Arbitrary Remote Code Execution when the API is exposed. There are endpoints that allow code execution, which can lead to exfiltration of service credentials.
CVE-2025-14774
UNKNOWNIncorrect Authorization vulnerability in ABB T-MAC Plus. This issue affects T-MAC Plus: 4.0-24.
CVE-2026-44654
UNKNOWNLibreChat is an enhanced ChatGPT clone that supports multiple AI providers. In versions up to and including 0.8.3, a shared-agent editor can delete file records through `DELETE /api/files` that the owner has reused across multiple agents. The deletion removes the file globally — not just from the shared agent — breaking the owner's other private agents that reference the same `file_id`. The private agent retains a stale `file_id` reference that no longer resolves. A shared-agent editor can destroy files that the owner uses across multiple agents. The owner's private agents — which the attacker has no access to — break silently with stale `file_id` references. This is a cross-agent integrity violation: editing access to one agent should not affect another. Version 0.8.4 contains a patch.
CVE-2026-35482
UNKNOWNalf.io is an open source ticket reservation system for conferences, trade shows, workshops, and meetups. Prior to version 2.0-M5-2606, a sandbox escape vulnerability in the alf.io extension script engine allows an authenticated administrator to execute arbitrary operating system commands on the server. The extension system is intended to execute restricted JavaScript in a sandboxed Rhino environment; however, a combination of an unguarded injected Java object (`returnClass`) and an incomplete AST blocklist allows the sandbox to be fully escaped using Java reflection without triggering any validation errors. Version 2.0-M5-2606 patches the issue.
CVE-2026-10616
MEDIUMA weakness has been identified in nextlevelbuilder GoClaw up to 3.11.3. The impacted element is the function TeamTasksTool.executeComplete of the file internal/tools/team_tasks_lifecycle.go of the component Team Task Completion Handler. Executing a manipulation can lead to missing authorization. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The project tagged the reported issue as bug.
CVE-2026-3514
UNKNOWNIn version 3.6.19 of prefecthq/prefect, an authentication bypass vulnerability exists due to the improper handling of URL path exemptions for health check probes. Specifically, the authentication middleware exempts any URL path ending with 'health' or 'ready' from authentication checks. This allows an attacker to create resources with names ending in 'health' or 'ready' and access them without authentication. Affected endpoints include those for variables, flows, work pools, work queues, and deployments. This vulnerability can lead to unauthorized access to sensitive information, such as API keys and database credentials, stored in Prefect Variables.
CVE-2026-9048
MEDIUMThe Slider Revolution plugin for WordPress is vulnerable to Sensitive Information Exposure in versions 7.0.0 - 7.0.14, via the 'slider.get.full' AJAX Action. This makes it possible for authenticated attackers, with Contributor-level access and above, to extract sensitive data including raw social media API credentials: the Instagram OAuth token, Flickr API key, YouTube Data API key, and Facebook App ID, stored in any configured slider's settings.
CVE-2025-32348
HIGHIn multiple locations, there is a possible background activity launch due to a missing permission check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
CVE-2026-22872
UNKNOWNCapsule is a multi-tenancy and policy-based framework for Kubernetes. The Capsule Controller runs with cluster-admin privileges. Although the TenantResource RawItems processing logic forcibly sets the namespace, this is ineffective for cluster-scoped resources. Prior to version 0.13.0, tenant administrators can leverage the Controller's elevated privileges to create cluster-scoped resources (such as ClusterRole and ValidatingWebhookConfiguration) that they cannot create directly, achieving cross-tenant privilege escalation and cluster-level attacks. The attack vector has a few limiting factors. This attack requires Tenant Owner privileges and requires Capsule Controller running with cluster-admin privileges (default configuration). Additionally, some clusters may have additional admission controllers blocking malicious resources. Version 0.13.0 patches this issue.
CVE-2026-45426
UNKNOWNExploitation requires the attacker to already be an authenticated Airflow worker holding a valid Log-server JWT issued for at least one Dag. Apache Airflow's Log server authorized JWT tokens against Dag IDs by applying Python's `str.lstrip()` to the requested path segment when verifying the JWT's `sub` claim. `str.lstrip()` strips any of a *set* of characters from the left (not a prefix), so a JWT issued for a Dag named e.g. `dag_a` would authorize log access to any other Dag whose name began with any subset of the characters `{d, a, g, _}` (e.g. `dag_attacker`, `aaaa_target`, `_dag_secret`). Such an authenticated worker could enumerate and read worker logs of other Dags whose names happened to share that character-class prefix, leaking task output and error traces beyond the documented per-Dag isolation boundary. Affects deployments relying on per-Dag log-access scoping (multi-team, shared-executor, shared-worker topologies). Users are advised to upgrade to `apache-airflow` 3.2.2 or later.
CVE-2026-10211
MEDIUMA vulnerability was determined in AstrBotDevs AstrBot 4.23.6. Affected by this issue is the function _normalize_rw_path of the file astrbot/core/tools/computer_tools/fs.py. This manipulation causes incorrect authorization. It is possible to initiate the attack remotely. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure but did not respond in any way.
CVE-2026-49376
UNKNOWNIn JetBrains TeamCity before 2026.1 insufficient username validation in the SAML plugin
CVE-2026-49369
UNKNOWNIn JetBrains YouTrack before 2026.1.13162 information disclosure was possible on Users and Groups pages
CVE-2026-48501
UNKNOWNGitHub CLI (gh) is GitHub’s official command line tool. Prior to 2.93.0, GitHub CLI incorrectly includes authorization header in API requests to TUF repository mirrors via gh attestation, gh release verify, and gh release verify-asset commands. The CLI uses a shared HTTP client with an authentication layer that automatically attaches tokens to outgoing requests. This layer lacks accurate host detection and can incorrectly attribute the target host, providing it with a token it should never receive. Specifically, the host normalization logic collapses any *.github.com subdomain to github.com, so a request to tuf-repo.github.com (a GitHub Pages site, not a GitHub API endpoint) is treated as a request to github.com and receives the user's github.com token. For hosts that don't match github.com or a known GHES instance at all, the resolver falls back to GH_ENTERPRISE_TOKEN if set. The gh attestation, gh release verify and gh release verify-asset commands fetch data from several external hosts as part of their normal operation (TUF metadata from tuf-repo.github.com and tuf-repo-cdn.sigstore.dev, artifact bundles from Azure Blob Storage). Because these requests go through the same authenticated HTTP client, the token is sent to all of them. This vulnerability is fixed in 2.93.0.
CVE-2026-35674
HIGHOpenClaw before 2026.5.18 contains a scope bypass vulnerability in the Gateway chat.send route that allows scoped clients to execute privileged commands. Attackers with operator.write scope can deliver commands through inherited external routes to bypass operator.approvals and operator.admin scope requirements, enabling unauthorized plugin, config, MCP, allowlist, and ACP mutations.
CVE-2026-35673
MEDIUMOpenClaw before 2026.4.29 contains an SSRF policy bypass vulnerability in browser debug and export routes that allows reuse of already-open blocked tabs. Attackers with access to these routes can bypass private-network SSRF policies by reusing blocked tabs to export or inspect content that should remain protected.
CVE-2026-34507
MEDIUMOpenClaw before 2026.4.29 contains a policy bypass vulnerability in QQBot admin commands that allows authenticated senders to skip DM-only and allowFrom policy checks. Attackers can route admin commands from unauthorized senders or contexts to execute restricted behavior that policy should have blocked.
CVE-2026-32906
MEDIUMOpenClaw before 2026.5.12 contains a privilege escalation vulnerability in Slack plugin approvals that allows exec-authorized users to resolve plugin approvals through the exec approver gate. Attackers with limited exec approval permissions can bypass intended approval splits to approve plugin actions outside operator configuration.
CVE-2026-9808
UNKNOWNAn authorization bypass vulnerability exists in the Mautic 7 API v2 endpoints (utilizing API Platform). Under certain conditions, roles configured with owner-scope restrictions (such as `viewown` or `editown`) are not properly enforced. This allows low-privilege authenticated API users to bypass ownership-logic controls and access or modify resources belonging to other users.
CVE-2026-49299
UNKNOWNIn OpenStack Neutron before 28.0.1, the tagging controller enforces plural policy action names on single-tag write operations while the defined policy rules use singular names. The mismatched names evaluate as allowed under the default policy, permitting a project reader to create and update tags on same-project resources. Deployments running Neutron 26.0.0 or later are affected.
CVE-2026-44882
UNKNOWNPortainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33., Portainer proxies requests to Kubernetes clusters through a middleware layer (kubeClientMiddleware) that validates the requesting user's token before forwarding traffic to the cluster. When security.RetrieveTokenData returned an error, the middleware wrote an HTTP 403 response but was missing a return statement — execution continued into the handler with a nil tokenData value. The Kubernetes endpoints sit behind Portainer's outer AuthenticatedAccess bouncer, so an attacker requires a valid Portainer session. However, a user whose secondary token validation fails in kubeClientMiddleware — for example a user without permission to access a given Kubernetes endpoint — would have their request forwarded to the cluster anyway, bypassing the authorization check. The same defect was present in both the CE and EE codebases. This vulnerability is fixed in 2.33.8.
CVE-2026-44850
UNKNOWNPortainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, Portainer offers an environment-level Disable bind mounts for non-administrators security setting that blocks regular users from binding host paths into containers they create through the Portainer-mediated Docker API. The check that enforces this setting only inspected the legacy HostConfig.Binds array on the container-create proxy and never looked at the equivalent HostConfig.Mounts array. Any authenticated user with rights to create containers on a Docker environment where the restriction is enabled could submit a bind-typed entry under HostConfig.Mounts and mount any host path into their container. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0.
CVE-2026-46823
UNKNOWNVulnerability in the Oracle Public Sector Financials (International) product of Oracle E-Business Suite (component: Authorization). Supported versions that are affected are 12.2.6-12.2.15. Easily exploitable vulnerability allows low privileged attacker with network access via HTTPS to compromise Oracle Public Sector Financials (International). While the vulnerability is in Oracle Public Sector Financials (International), attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle Public Sector Financials (International) accessible data. CVSS 3.1 Base Score 7.7 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N).
CVE-2026-42070
UNKNOWNMantis Bug Tracker (MantisBT) is an open source issue tracker. Prior to 2.28.2, the mc_issue_update() function in MantisBT allows users having update_bug_threshold access (UPDATER, with default settings) to edit, change view state, and modify time tracking on bugnotes belonging to other users — bypassing the default DEVELOPER (level 55) threshold required by the dedicated mc_issue_note_update() function. This vulnerability is fixed in 2.28.2.
CVE-2026-45042
UNKNOWNRustFS is a distributed object storage system built in Rust. Prior to 1.0.0-beta.2, improper authorization in the UploadPartCopy operation allows copying objects across buckets without enforcing destination bucket restrictions on allowed copy sources. The implementation validates GetObject permission on the source bucket and PutObject on the destination bucket independently, but does not enforce any policy constraints on whether the destination bucket permits the specified copy source. This enables unauthorized cross-bucket data movement. This vulnerability is fixed in 1.0.0-beta.2.
CVE-2026-44394
HIGHAn issue was discovered in OpenStack Keystone before 29.0.2. The Keystone federated token rescoping mechanism does not propagate the original token's expiry to the newly issued token. When a federated user rescopes a token via POST /v3/auth/tokens, the handle_scoped_token() function in the mapped authentication plugin returns response data without an expires_at value. The token provider falls back to issuing a token with a fresh default TTL. By rescoping repeatedly before each token expires, a user can maintain access indefinitely, bypassing operator-configured token lifetime policies. This is a variant of CVE-2012-3426. Only deployments using federated identity (SAML2, OpenID Connect) are affected.
CVE-2026-43000
HIGHAn issue was discovered in OpenStack Keystone before 29.0.2. When combined with an application credential impersonation vulnerability, an attacker with the member role on a project can escalate to admin by chaining unrestricted application credentials with Keystone trusts. The impersonated token carries the victim's identity, which passes the trustor validation check. Keystone then validates the delegated roles against the victim's actual role assignments in the database, not the roles on the requesting token. This allows the attacker to create a trust delegating the victim's admin role to themselves. The trust persists independently, and additional trusts and application credentials can be created to maintain access. All actions are logged under the victim's identity.
CVE-2026-42999
HIGHAn issue was discovered in OpenStack Keystone before 29.0.2. The Keystone RBAC policy enforcer in enforce_call unconditionally merges the raw JSON request body into the policy enforcement dictionary via policy_dict.update(json_input.copy()), overwriting trusted target data that was previously set from database lookups. Because flask.request.get_json is called with force=True, this works regardless of Content-Type or HTTP method. Any authenticated user can inject arbitrary policy target attributes (e.g., user_id, project_id) into the request body to bypass RBAC checks and perform unauthorized operations on resources belonging to other users or projects. This was introduced in commit 5ea59f52 (Rocky/14.0.0).
CVE-2026-42998
HIGHAn issue was discovered in OpenStack Keystone before 29.0.2. The Keystone application credential authentication plugin does not verify that the user supplied in the authentication request matches the owner of the application credential. An attacker can authenticate with their own application credential ID and secret while specifying a different user's name and domain in the request body. Keystone issues a token attributed to the victim user. The impersonated token is project-scoped and carries the intersection of the application credential's roles and the victim's actual roles on the project. This enables audit evasion, reading the victim's credentials, and acting as the victim within shared projects.
CVE-2026-45297
UNKNOWNOpenReplay is a self-hosted session replay suite. Prior to 1.26.0, there is a cross-tenant IDOR on feature-flag and assist-stats routes via {project_id} case mismatch. ProjectAuthorizer.__call__ (OSS api/auth/auth_project.py:14-38 and EE ee/api/auth/auth_project.py:14-46) only runs projects.is_authorized(project_id, tenant_id, user_id) + projects.get_project(tenant_id, project_id) when self.project_identifier == "projectId" (camelCase). For EE multi-tenant, feature-flag queries only filter on project_id, never tenant_id. Any authenticated user in tenant A can read/update/delete feature-flag rows belonging to tenant B by iterating the sequential integer project_id + feature_flag_id. OSS is single-tenant by design ({"errors":["tenants already registered"]} on second signup) so there's no cross-tenant impact This vulnerability is fixed in 1.26.0.
CVE-2026-40914
MEDIUMA vulnerability exists in Apache Artemis whereby an application using the STOMP protocol with security credentials that grant either the consume or send permission on an address can augment the routing-type supported by that address even if said user doesn't have the createAddress permission for that particular address. A user could successfully send a message to an address or consume a message from a queue with a routing-type not supported by the corresponding address when that operation should actually be rejected on the basis that the user doesn't have permission to change the routing-type of the address. Even though the user was already granted permission to send and/or consume messages, they should not be able to augment the routing-type of the address without the createAddress permission. This issue affects Apache Artemis: from 2.50.0 through 2.53.0; Apache ActiveMQ Artemis: from 2.0.0 through 2.44.0. Users are recommended to upgrade to version 2.54.0, which fixes the issue.
CVE-2026-9807
UNKNOWNGitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.9 before 18.10.7, 18.11 before 18.11.4, and 19.0 before 19.0.1 that under certain conditions could have allowed a blocked Project Access Token to continue accessing private resources due to incorrect authorization enforcement.
CVE-2026-9791
MEDIUMA flaw was found in Keycloak. An authenticated user with existing organization membership can exploit this flaw by accessing user-facing APIs, such as the account API or by requesting an OpenID Connect (OIDC) token with the 'organization' scope. This allows organization metadata to be disclosed in tokens, even after an administrator has explicitly disabled the Organizations feature, potentially leading to incorrect authorization decisions by resource servers.
CVE-2026-48064
UNKNOWNpam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.1, when a PAM service is configured with deny_remote=false in pam_usb (commonly done for display managers such as gdm-password or lightdm to bypass process/TTY heuristics for local sessions), the PAM_RHOST check in pusb_do_auth() is also skipped. PAM_RHOST is set by remote daemons (sshd, XDMCP servers) to identify the remote client address. Because the check is gated inside if (opts.deny_remote), a genuine remote XDMCP connection reaches the USB device authentication step instead of being rejected. This vulnerability is fixed in 0.9.1.
CVE-2026-45108
UNKNOWNHimmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. From 2.0.0 to before 3.1.5 and 2.3.11, Himmelblau contained an authentication bypass vulnerability in the Device Authorization Grant (DAG) flow that allowed a user within the same Entra ID domain to obtain a local Unix session as another user by providing their own valid credentials. The vulnerability existed in the token_validate function, which validated domain aliases for legitimate multi-domain scenarios but failed to verify that the local part (username) of the authenticated user's UPN matched the requested account username. The function only compared domains, not the complete usernames. This vulnerability is fixed in 3.1.5 and 2.3.11.
CVE-2026-44681
UNKNOWNAuthlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.6.12 and 1.7.1, an unauthenticated open redirect in Authlib's OpenIDImplicitGrant and OpenIDHybridGrant authorization endpoint lets a remote attacker cause the authorization server to issue an HTTP 302 to an attacker-chosen URL by submitting an authorization request that omits the openid scope. This vulnerability is fixed in 1.6.12 and 1.7.1.
CVE-2026-6713
UNKNOWNGitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.2 before 18.10.7, 18.11 before 18.11.4, and 19.0 before 19.0.1 that under certain conditions could have allowed an unauthorized user to enumerate private projects due to incorrect authorization checks.
CVE-2026-48152
UNKNOWNBudibase is an open-source low-code platform. Prior to 3.39.0, the single-datasource GET and PUT routes are guarded by generic TABLE READ, not by Builder/Admin permission or datasource-specific ownership/resource checks. The built-in Basic app user role maps to the WRITE permission set, which includes table read/write and query write. A Basic user can therefore read an existing REST datasource, receive redacted authConfigs values, submit an update that changes only config.url while keeping the redacted placeholders, and trigger an existing saved relative-path REST query. During update, mergeConfigs() restores the old stored secret when it sees the redaction placeholder. During query execution, Budibase prefixes the attacker-controlled datasource config.url to the relative query path and applies the resolved stored auth headers. The result is server-side disclosure of the builder-configured REST Authorization secret to an attacker-controlled listener. This vulnerability is fixed in 3.39.0.
CVE-2026-45718
UNKNOWNBudibase is an open-source low-code platform. Prior to 3.38.1, the row action trigger endpoint (POST /api/tables/:sourceId/actions/:actionId/trigger) fails to validate that the user-supplied rowId is within the scope of the view's row filters. A user with access to a filtered view can trigger row actions on any row in the underlying table, including rows explicitly excluded by the view's security filters. This vulnerability is fixed in 3.38.1.
CVE-2026-45081
UNKNOWNFrappe HR is an open-source human resources management solution (HRMS). Prior to 16.5.0, authenticated employees could access other employees’ leave details due to improper authorization checks. This vulnerability is fixed in 16.5.0.
CVE-2026-44473
UNKNOWNElla Core is a 5G core designed for private networks. Prior to 1.10.0, a radio with a valid NG Setup can send a forged PDUSessionResourceSetupResponse carrying any UE's AMF-UE-NGAP-ID. Ella Core does not verify the message arrived on the SCTP association bound to that UE's logical NG-connection, then creates a GTP tunnel towards that radio. This vulnerability is fixed in 1.10.0.
CVE-2026-44330
UNKNOWNfree5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-pfdmanagement route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can use a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token) to read PFD application data via GET /applications and GET /applications/{appID}, and to create or delete PFD change-notification subscriptions via POST /subscriptions and DELETE /subscriptions/{subID}. Same root cause as the other NEF SBI findings: the route group is mounted without any inbound auth middleware. Unlike the OAM and traffic-influence groups, nnef-pfdmanagement IS declared in the runtime ServiceList, so this is the production-intended path that operators expect to be protected by OAuth2 setting receive from NRF: true -- and it is not. This vulnerability is fixed in 4.2.2.
CVE-2026-44838
UNKNOWNRabbitMQ is a messaging and streaming broker. From 4.2.0 to before 4.2.4, RabbitMQ's MQTT plugin allows for topic-level authorization using regular expressions with variable substitution. Administrators can create patterns such as ^{client_id}-sensors$ to restrict user access to topics that include their client ID. However, the client_id is provided by the user in the MQTT CONNECT packet and is inserted into the regex pattern without escaping special regex characters. This flaw enables an authenticated MQTT user to inject regex operators to bypass authorization. This vulnerability is fixed in 4.2.4 and 4.3.0.