Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NSummary
CVE-2026-39374 is a medium-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Plane Plane. Its CVSS base score is 6.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 11th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-3 (Access Enforcement) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-39374 affects Plane, an open-source project management tool, in versions prior to 1.3.0. The vulnerability resides in the IssueBulkUpdateDateEndpoint, which permits authenticated project members with ADMIN or MEMBER roles to modify the start_date and target_date fields of any issue across the entire Plane instance. This occurs because the endpoint fetches issues by ID without enforcing filters for workspace or project membership, resulting in unauthorized cross-boundary data modification. The issue is classified under CWE-639 (Authorization Bypass Through User-Controlled Key) with a CVSS v3.1 base score of 6.5 (AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N).
An attacker with low-privilege access as a project ADMIN or MEMBER can exploit this vulnerability remotely over the network with low complexity and no user interaction required. By sending crafted requests to the endpoint with issue IDs from other workspaces or projects, the attacker can alter date fields on issues they do not own or have permission to access, potentially disrupting project timelines, falsifying progress reports, or enabling further privilege escalation in multi-tenant environments.
The vulnerability was fixed in Plane version 1.3.0, as detailed in the GitHub security advisory at https://github.com/makeplane/plane/security/advisories/GHSA-4q54-h4x9-m329. Security practitioners should upgrade to 1.3.0 or later and review access controls on bulk update endpoints in similar project management tools.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19913
Vulnerability Data
Plane is an an open-source project management tool. Prior to 1.3.0, the IssueBulkUpdateDateEndpoint allows a project member (ADMIN or MEMBER) to modify the start_date and target_date of ANY issue across the entire Plane instance, regardless of workspace or project membership.…
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The endpoint fetches issues by ID without filtering by workspace or project, enabling cross-boundary data modification. This vulnerability is fixed in 1.3.0.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Enforcing approved authorizations on every access request structurally stops a user-controlled key from reaching another user's data.
Requiring explicit access-control decisions on each request blocks unauthorized key-driven access.
Least-privilege restrictions limit the scope of data reachable even if a key check is bypassed.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.
Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect missing authorization checks but does not prevent the weakness in production.
Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.
Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.
Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.
Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.
Secure development lifecycle includes authorization design but does not itself implement runtime access checks.