---
cve: "CVE-2026-66877"
severity: "HIGH"
cvss: 8.1
epss: "0.4%"
vendor: "Gitea"
kev: false
exploited: false
published: "2026-10-14 15:17:21"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T11:46:21+01:00"
---

# CVE-2026-66877

> 8.1 HIGH · 🧪 PoC

## Beschreibung

Gitea enforces first-time fork contributor approval by blocking jobs, but some job transition and dispatch paths do not re-check the run's approval requirement. A separate run sharing a job-level concurrency group can cancel a pending job and cause its blocked sibling jobs to be re-emitted and dispatched without approval. This allows unreviewed workflow code to execute on self-hosted runners; fork secrets remain withheld and the run token remains read-only.

## CNA-Record (Kanon, cvelistV5)

- CNA: **Gitea**
- State: PUBLISHED
- Stand: 2026-10-15 03:56:53

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **total**

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Keine | good |

## Schwachstellen-Klasse

- **CWE-284** — Improper Access Control
  The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

## Angriffsmuster (CAPEC)

- [CAPEC-19 — Embedding Scripts within Scripts](https://capec.mitre.org/data/definitions/19.html) _(Severity: High)_
- [CAPEC-441 — Malicious Logic Insertion](https://capec.mitre.org/data/definitions/441.html) _(Severity: High)_
- [CAPEC-478 — Modification of Windows Service Configuration](https://capec.mitre.org/data/definitions/478.html) _(Severity: High)_
- [CAPEC-479 — Malicious Root Certificate](https://capec.mitre.org/data/definitions/479.html) _(Severity: Low)_
- [CAPEC-502 — Intent Spoof](https://capec.mitre.org/data/definitions/502.html)
- [CAPEC-503 — WebView Exposure](https://capec.mitre.org/data/definitions/503.html)
- [CAPEC-536 — Data Injected During Configuration](https://capec.mitre.org/data/definitions/536.html) _(Severity: High)_
- [CAPEC-546 — Incomplete Data Deletion in a Multi-Tenant Environment](https://capec.mitre.org/data/definitions/546.html) _(Severity: Medium)_

## ATT&CK-Techniken

- [T1027.009 — Obfuscated Files or Information: Embedded Payloads](https://attack.mitre.org/techniques/T1027/009/)
- [T1546.004 — Event Triggered Execution:.bash_profile and .bashrc](https://attack.mitre.org/techniques/T1546/004/)
- [T1546.016 — Event Triggered Execution: Installer Packages](https://attack.mitre.org/techniques/T1546/016/)
- [T1574.011 — Hijack Execution Flow:Service Registry Permissions Weakness](https://attack.mitre.org/techniques/T1574/011/)
- [T1543.003 — Create or Modify System Process:Windows Service](https://attack.mitre.org/techniques/T1543/003/)
- [T1553.004 — Subvert Trust Controls:Install Root Certificate](https://attack.mitre.org/techniques/T1553/004/)

## Patch verfügbar (OSV)

- 146cc3eec57174711eac0e0a0c7b38670c6e3922 (Commit)

## BSI-Hinweise (deutsch)

- [Gitea: Mehrere Schwachstellen ermöglichen Ausführen von beliebigem Programmcode](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-3079) — _BSI-Einstufung: hoch_
  Ein Angreifer kann mehrere Schwachstellen in Gitea ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder Denial-of-Service-Zustände zu verursachen.

## Referenzen

- <https://github.com/go-gitea/gitea/security/advisories/GHSA-v2w8-m4gr-qj65>
- <https://blog.gitea.com/release-of-1.27.3/>
- <https://github.com/go-gitea/gitea/pull/39005>
- <https://github.com/go-gitea/gitea/pull/39018>
- <https://github.com/go-gitea/gitea/releases/tag/v1.27.3>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-66877/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_