Skip to content

Instantly share code, notes, and snippets.

@alon710
Created January 24, 2026 21:22
Show Gist options
  • Select an option

  • Save alon710/c04d0150fe6489cd6aa0244c5949dba1 to your computer and use it in GitHub Desktop.

Select an option

Save alon710/c04d0150fe6489cd6aa0244c5949dba1 to your computer and use it in GitHub Desktop.
CVE-2026-20888: Unscheduled Disruption: Killing Gitea Auto-Merges via logic Flaws - CVE Security Report

CVE-2026-20888: Unscheduled Disruption: Killing Gitea Auto-Merges via logic Flaws

CVSS Score: 4.3 Published: 2026-01-23 Full Report: https://cvereports.com/reports/CVE-2026-20888

Summary

A logic flaw in Gitea's access control allows any user with read access to a repository to cancel scheduled auto-merges, effectively enabling low-privileged users to disrupt CI/CD workflows and release pipelines.

TL;DR

In Gitea versions up to 1.25.3, the 'Scheduled Auto-Merge' feature lacked proper authorization checks on its cancellation endpoints. This means any user with read access (even a lowly intern or a random public user) could cancel a maintainer's scheduled merge, causing silent delays in deployment. Fixed in v1.25.4 by enforcing strict permission checks.

Exploit Status: POC

Technical Details

  • CWE ID: CWE-862
  • Attack Vector: Network
  • CVSS: 4.3 (Medium)
  • Impact: Integrity (Low)
  • Privileges: Low (Read Access)
  • Exploit Status: PoC Available

Affected Systems

  • Gitea < 1.25.4
  • Gitea: <= 1.25.3 (Fixed in: 1.25.4)

Mitigation

  • Upgrade Gitea to version 1.25.4 or later.
  • Restrict repository visibility to trusted users until patched.
  • Monitor audit logs for unexpected auto-merge cancellations.

Remediation Steps:

  1. Backup your Gitea configuration and database.
  2. Download the 1.25.4 binary or pull the latest docker image (gitea/gitea:1.25.4).
  3. Replace the binary/container and restart the service.
  4. Verify the fix by attempting to cancel an auto-merge as a low-privileged user.

References


Generated by CVEReports - Automated Vulnerability Intelligence

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment