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CVE-2026-20897 Gitea CVE debrief

CVE-2026-20897 is a critical vulnerability in Gitea, a popular open-source Git repository manager. The issue arises from Gitea's improper validation of repository ownership when deleting Git LFS (Large File Storage) locks. This flaw allows a user with write access to one repository to potentially delete LFS locks belonging to other repositories, which could lead to data integrity issues and unauthorized access to sensitive files. The vulnerability has been rated with a CVSS score of 9.1, indicating a high severity level. Gitea has addressed this issue in version 1.25.4. Users are strongly advised to update to this version or apply the provided patches to mitigate the risk.

Vendor
Gitea
Product
Gitea Open Source Git Server
CVSS
CRITICAL 9.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-01-22
Original CVE updated
2026-07-15
Advisory published
2026-01-22
Advisory updated
2026-07-15

Who should care

System administrators and developers using Gitea for Git repository management should be aware of this vulnerability. Specifically, those who have Gitea installations with multiple users or repositories, or where users have write access to certain repositories, are at risk. Additionally, organizations relying on Gitea for storing sensitive or critical code should prioritize updating to the patched version to prevent potential data breaches or integrity issues.

Technical summary

The vulnerability in Gitea stems from inadequate validation of repository ownership during the deletion of Git LFS locks. Normally, repository permissions are designed to prevent users from affecting resources outside their designated repositories. However, due to this flaw, an authenticated user with write access to a repository could exploit this vulnerability to delete LFS locks from other repositories they do not own or have write access to. This could lead to unintended data modifications or exposure. The issue is addressed in Gitea version 1.25.4, where proper validation has been implemented to prevent such unauthorized actions.

Defensive priority

High. Given the critical CVSS score of 9.1 and the potential for data integrity and confidentiality impacts, defenders should treat this vulnerability with high priority. Immediate action is recommended to ensure Gitea instances are updated to version 1.25.4 or patched accordingly.

Recommended defensive actions

  • Update Gitea to version 1.25.4 or later.
  • Apply patches provided in the Gitea release notes or associated issue tracking links.
  • Review repository permissions and access controls to ensure principle of least privilege.
  • Monitor Gitea instances for unusual activity related to LFS locks.
  • Consider implementing additional logging and monitoring for sensitive repository operations.

Evidence notes

The CVE-2026-20897 details were obtained from the official CVE record and the National Vulnerability Database (NVD). Additional information was gathered from Gitea's official release notes and issue tracking system. The CVSS score and vector were provided by the NVD, indicating a critical severity level.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-20897 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-20897

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-20897 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-20897

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://blog.gitea.com/release-of-1.25.4/

    88ee5874-cf24-4952-aea0-31affedb7ff2 - Release Notes

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://github.com/go-gitea/gitea/pull/36344

    88ee5874-cf24-4952-aea0-31affedb7ff2 - Issue Tracking, Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://github.com/go-gitea/gitea/pull/36349

    88ee5874-cf24-4952-aea0-31affedb7ff2 - Issue Tracking, Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://github.com/go-gitea/gitea/releases/tag/v1.25.4

    88ee5874-cf24-4952-aea0-31affedb7ff2 - Release Notes

  • Source reference

    Unverified legacy reference

    URL: https://github.com/go-gitea/gitea/security/advisories/GHSA-rrq5-r9h5-pc7c

    88ee5874-cf24-4952-aea0-31affedb7ff2 - Broken Link

  • Source reference

    Unverified legacy reference

    URL: https://access.redhat.com/security/cve/CVE-2026-20897

    0b0ca135-0b70-47e7-9f44-1890c2a1c46c

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.