Gitea: Denial of Service via Unbounded io.ReadAll in NPM Package Tag Endpoint

Exploitation

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

CVSS

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

EPSS

• CVE-2026-42931: 0.53% estimated exploitation activity in the next 30 days; percentile 44.90 (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 An unbounded io.ReadAll(ctx.Req.Body) call in the NPM package tag API endpoint allows any authenticated user to crash the Gitea server by sending a single large HTTP request. The request body is read entirely into memory with no size limit, causing an Out-of-Memory (OOM) kill. With concurrent requests, the attack produces a persistent denial of service that survives automatic restarts. Details The AddPackageTag function reads the entire HTTP request body into memory using io.ReadAll() with no size validation: This route is registered at routers/api/packages/api.go:433: Why this causes OOM and not just a slow request: In Go, io.ReadAll() reads into a []byte that grows dynamically. When the incoming data exceeds available memory, the Go runtime attempts to allocate a larger backing array. This allocation fails, triggering an unrecoverable runtime.throw("out of memory") that kills the entire process, not just the goroutine handling the request. No server-side size limits apply…

Published by the source

21 Jul 2026, 20:39 UTC

Last modified by the source

21 Jul 2026, 20:39 UTC

Source last checked

26 Oct 2026, 15:27 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-wwqq-x6w4-frm2

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# Patch Next advisory brief: CVE-2026-42931

Advisory: Gitea: Denial of Service via Unbounded io.ReadAll in NPM Package Tag Endpoint
IDs: CVE-2026-42931, GHSA-wwqq-x6w4-frm2
Record: https://patchnext.com/advisories/cve-2026-42931 (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: Medium (CVSS 6.5)
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 1.27.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.gitea.io/gitea: affected < 1.27.0; fixed in 1.27.0

## 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-wwqq-x6w4-frm2 (GitHub-reviewed advisory GHSA-wwqq-x6w4-frm2 lists affected ranges: Go code.gitea.io/gitea >=0 <1.27.0)

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