What is CVE-2026-20896?

CVE-2026-20896 is a critical-severity vulnerability in Gitea Open Source Git Server, classified under Improper Access Control. CVSS score: 9.8/10. Published 2026-07-03.

How severe is CVE-2026-20896?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-20896 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Gitea Open Source Git Server

CVE-2026-20896

Gitea Docker image versions up to and including 1.26.2 use REVERSE_PROXY_TRUSTED_PROXIES=* by default, allowing any source IP to impersonate a user when reverse-proxy authentication headers such as X-WEBAUTH-USER are enabled.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Gitea Open Source Git Server — versions 0

Weakness classification (CWE)

CWE-284 — Improper Access Control

Public proof-of-concept exploits

kaleth4/CVE-2026-20896

References

88ee5874-cf24-4952-aea0-31affedb7ff2 (vendor-advisory)
88ee5874-cf24-4952-aea0-31affedb7ff2 (patch)
88ee5874-cf24-4952-aea0-31affedb7ff2 (release-notes)
88ee5874-cf24-4952-aea0-31affedb7ff2 (release-notes)

Frequently asked questions

What is CVE-2026-20896?: CVE-2026-20896 is a critical-severity vulnerability in Gitea Open Source Git Server, classified under Improper Access Control. CVSS score: 9.8/10. Published 2026-07-03.
How severe is CVE-2026-20896?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-20896 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.