---
title: "CVE-2026-27780: Gitea pre-receive hook scanner errors allow branch-protection bypass"
url: https://erroneo.us/security/cve/CVE-2026-27780/
description: "CVE-2026-27780 (code.gitea.io/gitea (Go)): Gitea versions before 1.26.0 do not fail closed on bufio.Scanner errors while processing pre-receive hook input…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-03
date_modified: 2026-09-01
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-27780"
kev: false
cvss: 9.8
epss: 0.00638
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-27780: Gitea pre-receive hook scanner errors allow branch-protection bypass

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.6% , percentile 50: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 50% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes code.gitea.io/gitea (Go) < 1.26.0, fixed in 1.26.0 . Check your lockfile, including transitive dependencies.

## What it is

Gitea versions before 1.26.0 do not fail closed on bufio.Scanner errors while processing pre-receive hook input, allowing oversized input to bypass branch-protection checks.

## Affected packages

- Go `code.gitea.io/gitea` < 1.26.0 → fixed: 1.26.0

## Affected products (CVE record)

- Gitea Gitea Open Source Git Server: < 1.26.0

## Severity

- CISA-ADP CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.64% probability of exploitation activity in the next 30 days; percentile 50.

## Sources

- [GitHub Pull Request #36963](https://github.com/go-gitea/gitea/pull/36963)
- [Gitea v1.26.0 Release](https://github.com/go-gitea/gitea/releases/tag/v1.26.0)
- [Gitea v1.26.0 Release Blog Post](https://blog.gitea.com/release-of-1.26.0/)
- [GitHub Advisory GHSA-vhq7-fwwh-7hjf](https://github.com/advisories/GHSA-vhq7-fwwh-7hjf)
- [CVE.org record CVE-2026-27780](https://www.cve.org/CVERecord?id=CVE-2026-27780)
- [NVD entry CVE-2026-27780](https://nvd.nist.gov/vuln/detail/CVE-2026-27780)
- [github.com](https://github.com/go-gitea/gitea/commit/c453d09c36fad094405314dba2f370434b200711)

---
Source page: https://erroneo.us/security/cve/CVE-2026-27780/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt