Vulnerability in code.gitea.io/gitea (CVE-2026-26247)
Summary
Vulnerability in code.gitea.io/gitea (CVE-2026-26247). Confidential information can be exposed externally. Mitigation: upgrade to 1.25.5 or later.
Original description
The description as published by the source.
Gitea versions before 1.25.5 do not persist the OAuth2 PKCE S256 challenge method correctly during authorization, allowing token exchange without the expected verifier check.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-26247 has been found in code.gitea.io/gitea.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade code.gitea.io/gitea to 1.25.5 or later.
If unsure, ask your IT team or search "code.gitea.io/gitea CVE-2026-26247" on the vendor's site.
CVE-2026-26247 (code.gitea.io/gitea) — CWE-284 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 1.25.5 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-284) exists in code.gitea.io/gitea.
Check the vendor advisory for the affected versions of code.gitea.io/gitea.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to 1.25.5.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'code.gitea.io/gitea' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'code.gitea.io/gitea' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
code.gitea.io/giteaを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade code.gitea.io/gitea to 1.25.5ステージング環境で 1.25.5 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com
- web github.com
- web blog.gitea.com
- web github.com
- web blog.gitea.com
- web github.com
- web github.com