CVE-2026-58436 ParseAcceptLanguage quadratic-time DoS via Locale middleware on unauthenticated requests
Attackers can cause denial of service in Gitea by sending crafted Accept-Language headers to unauthenticated endpoints, triggering quadratic-time parsing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-58436?
CVE-2026-58436 is a high-severity denial of service vulnerability in Gitea Open Source Git Server, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ParseAcceptLanguage quadratic-time DoS via Locale middleware on unauthenticated requests
Which versions are affected by CVE-2026-58436?
3 open source packages ship an affected version, including code.gitea.io/gitea and gitea.dev.
| Package | Affected | Fixed in |
|---|---|---|
code.gitea.io/gitea Go | All versions | 1.27.0 |
code.gitea.io/gitea Go | All versions | 1.27.0 |
gitea.dev Go | All versions | 1.27.0 |
How do I fix CVE-2026-58436?
Upgrade code.gitea.io/gitea to 1.27.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-58436 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-58436 exists.
Sources
Also known as GHSA-fw57-jgch-pgf3, GO-2026-6055, MINI-68qj-cqgp-8pjv, MINI-prj2-vpfp-8v88.