DNS Bypass in Gitea Affected by Allow Domain Misconfiguration
CVE-2026-101027

7.7HIGH

Key Information:

Vendor

Gitea

Status
Gitea
Vendor
CVE Published:
6 October 2026

What is CVE-2026-101027?

This vulnerability arises when the [migrations] ALLOWED_DOMAINS setting is configured improperly. In this case, a hostname from the allow list can be accepted without validating its resolved address against local network restrictions. An attacker who is able to initiate repository migrations and manipulate the DNS for an allowed hostname could redirect it to loopback or private addresses. This misconfiguration allows unauthorized access to internal services via the Gitea server. Instances that do not have ALLOWED_DOMAINS set up are not influenced by this specific bypass.

Affected Version(s)

Gitea 0 <= 1.27.3

References

https://github.com/go-gitea/gitea/security/advisories/GHS...
vendor-advisory
https://github.com/go-gitea/gitea/pull/39426
patch
https://blog.gitea.com/release-of-28.0.0/
release-notes

CVSS V3.1

Score:
7.7
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

https://github.com/Razzlemouse
https://github.com/TheFox0x7
https://github.com/silverwind
https://github.com/bircni
https://github.com/wxiaoguang
.