Gitea: Incomplete SSRF Protection in Webhook and Migration Allow-list Default Filter

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-22874: 0.46% estimated exploitation activity in the next 30 days; percentile 40.23 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Gitea's default SSRF allow-list (MatchBuiltinExternal, used by both webhook delivery and repository migrations) relies on Go's standard library net.IP.IsPrivate(), which only covers RFC 1918 and RFC 4193. As a result, several IP ranges commonly used for cloud metadata services, internal networks, and IPv6 transition mechanisms are not blocked, allowing authenticated users to send HTTP requests to those destinations and read the responses via the webhook history UI. Details The vulnerability lives in HostMatchList.checkIP, specifically line 103: net.IP.IsPrivate() recognises only: - 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 (RFC 1918) - fc00::/7 (RFC 4193 IPv6 ULA) It does not recognise: | Range | Description | |---|---| | 100.64.0.0/10 | RFC 6598 Carrier-Grade NAT | | 168.63.129.16/32 | Azure WireServer metadata endpoint | | 172.32.0.0/11 | Non-RFC1918 portion of 172.0.0.0/8 (real-world internal use) | | 64:ff9b::/96 | RFC 6052 IPv6 NAT64 (can embed 169.254.169.254) | |…

Published by the source

21 Jul 2026, 20:27 UTC

Last modified by the source

21 Jul 2026, 20:27 UTC

Source last checked

26 Oct 2026, 15:27 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-2r5c-gw76-rh3w

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# Patch Next advisory brief: CVE-2026-22874

Advisory: Gitea: Incomplete SSRF Protection in Webhook and Migration Allow-list Default Filter
IDs: CVE-2026-22874, GHSA-2r5c-gw76-rh3w
Record: https://patchnext.com/advisories/cve-2026-22874 (revision 1, source checked 26 Oct 2026, 15:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code.gitea.io/gitea 1.26.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.gitea.io/gitea: affected < 1.26.3; fixed in 1.26.3

## Suggested inspection (read-only)
- Go code.gitea.io/gitea: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on code.gitea.io/gitea.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-2r5c-gw76-rh3w (GitHub-reviewed advisory GHSA-2r5c-gw76-rh3w lists affected ranges: Go code.gitea.io/gitea >=0 <1.26.3)

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