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 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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
https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4

Configurations

No configuration.

History

07 Jul 2026, 18:16

Type	Values Removed	Values Added
References	~~() https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4 -~~	() https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4 -

03 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-03 21:16

Updated : 2026-07-07 18:16

NVD link : CVE-2026-20896

Mitre link : CVE-2026-20896

CVE.ORG link : CVE-2026-20896

JSON object : View

Products Affected

No product.

CWE

CWE-284

Improper Access Control

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