CVE-2026-20896

Description

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 v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0078

Probability of exploitation

0.52%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-284 CWE-284

References

Other References

https://blog.gitea.com/release-of-1.26.3-and-1.26.4/ https://github.com/go-gitea/gitea/pull/38151 https://github.com/go-gitea/gitea/releases/tag/v1.26.3 https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-20896? +

CVE-2026-20896 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0078, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-20896? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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