CVE-2026-42844
Published: 12 May 2026
Summary
CVE-2026-42844 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Getgrav Grav. Its CVSS base score is 8.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 25.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-29857
Vulnerability details
Grav is a file-based Web platform. In Grav 2.0.0-beta.2, a low-privileged authenticated API user with api.media.write can abuse /api/v1/blueprint-upload to write an arbitrary YAML file into user/accounts/, then log in as the newly created account with api.super privileges. This results…
more
in full administrative compromise of the Grav API. This vulnerability is fixed in API 1.0.0-beta.17.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Authenticated low-priv user abuses unrestricted YAML file upload (CWE-434) into accounts/ dir to create a new api.super account, directly enabling local privilege escalation (T1068) via new account creation (T1136).
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Policy addresses roles, responsibilities, and privilege management to prevent improper privilege assignments.
Access supervision ensures privileges are assigned and managed without improper escalation or retention.
Assigning group/role memberships and access authorizations (privileges) while reviewing accounts addresses improper privilege management.
Enforces proper privilege management by requiring all decisions through the verified reference monitor.
By mandating division of duties across roles, the control enforces proper privilege management and prevents a single entity from controlling an entire sensitive process.
Implements core proper privilege management by restricting to only required rights.
Policy requires training on privilege management and least privilege, making it harder to exploit improper privilege management weaknesses.
Training covers proper privilege management practices, making incorrect privilege assignments less likely.