---
id: "CVE-2026-113429"
kind: "vulnerability"
aliases: ["CVE-2026-113429"]
title: "Gitea: Actions artifact downloads let uploaded HTML run scripts on the origin"
severity: "high"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: [{"name": "gitea", "fixed": ["28.3.0"], "affected": "< 28.3.0", "ecosystem": "vendor"}]
ecosystems: []
tags: ["actions", "gitea", "runtime", "self-hosted", "xss"]
not_affected_if: ["actions-disabled", "no-legacy-artifacts"]
published_at: "2026-11-01T10:18:34+00:00"
first_seen_at: "2026-11-01T10:49:32+00:00"
updated_at: "2026-11-01T10:53:42+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-113429", "first_seen_at": "2026-11-01T10:49:32+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-11-01T10:53:42+00:00"}]
---

# Gitea: Actions artifact downloads let uploaded HTML run scripts on the origin

Legacy Gitea Actions artifact uploads (v1 to v3) stored the request's Content-Encoding header unchecked as the served Content-Type, and a video/ or audio/ value also removed the sandboxing Content-Security-Policy. An attacker who can run an Actions job can make a browser execute script on the Gitea origin with a victim's session, which for an administrator means control of the instance.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:gitea affected < 28.3.0 fixed 28.3.0

## How to check

Check your Gitea version (Site Administration > Overview, or 'gitea --version'); anything below 28.3.0 is affected if Actions is enabled. Also check whether Actions artifacts uploaded via legacy upload-artifact v1 to v3 exist.

## Fix

Upgrade Gitea to 28.3.0 or later

## Timeline

- 2026-11-01T10:49:32+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-113429
- 2026-11-01T10:53:42+00:00 analyst — Gitea release blog (vendor) lists CVE-2026-113429 fixed in 28.3.0 via #39855/#39996; NVD range 0 < 28.3.0. Advisory GHSA page unreadable by web-cli. No PoC/exploitation found; backports to older series not stated.

## Documents

- [advisory] Gitea 28.3.0 is released (security section) https://blog.gitea.com/release-of-28.3.0/
- [describes] NVD CVE-2026-113429 https://nvd.nist.gov/vuln/detail/CVE-2026-113429
- [fix] fix(actions): drop untrusted Content-Encoding from v1 artifact uploads (#39855) https://git.trackers.run/public/gitea/commit/4f744d15be035b228e424a5384c81707b3792ead

## From the sources

Legacy (v1 to v3) Actions artifact uploads stored the request's `Content-Encoding` header unchecked in the column that is served as the artifact's `Content-Type` on download, and a value starting with `video/` or `audio/` also removed the sandboxing Content-Security-Policy. A user who can run an Actions job could upload an artifact that a browser renders as HTML on the Gitea origin when the direct artifact download URL is opened, and the URL is reachable anonymously on public repositories. A victim who opens the link runs the attacker's script with their own session, which for an administrator means control of the instance. Legacy uploads now store only the `gzip` marker, and the special serve headers are chosen only for valid media types.

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