CVE-2026-23603 Blind SSRF in OAuth2 avatar synchronization via unvalidated OIDC picture claim
Attackers can trigger blind SSRF in Gitea by manipulating OIDC picture claims during avatar synchronization, potentially accessing internal resources.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23603?
CVE-2026-23603 is a low-severity server-side request forgery vulnerability in Gitea Open Source Git Server, published on 13 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Blind SSRF in OAuth2 avatar synchronization via unvalidated OIDC picture claim
Weakness: CWE-918
Which versions are affected by CVE-2026-23603?
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-2026-23603?
Upgrade code.gitea.io/gitea to 1.27.0 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-23603 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-23603 exists.
Sources
Also known as GHSA-x77v-q46j-393g, GO-2026-6083, MINI-835r-xp73-p6j4, MINI-frhp-29v2-h3j4.