Improper Certificate Validation in Cosign

Exploitation

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

CVSS

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

EPSS

• CVE-2022-23649: 0.16% estimated exploitation activity in the next 30 days; percentile 5.48 (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.

Impact Cosign can be manipulated to claim that an entry for a signature exists in the Rekor transparency log even if it doesn't. This requires the attacker to have pull and push permissions for the signature in OCI. This can happen with both standard signing with a keypair and "keyless signing" with Fulcio. Signing with a keypair <details To reproduce this vulnerability, create a keypair and sign an image. Don't store the signature in Rekor: If an attacker has access to the signature in OCI, they can manipulate cosign into believing the entry was stored in Rekor even though it wasn't. To accomplish this, the attacker needs to: 1. Pull the signature image 2. Annotate the signature image with any valid Rekor bundle under the dev.sigstore.cosign/bundle annotation 3. Push the signature image back to OCI Verification then prints out the following: The claim that Existence of the claims in the transparency log was verified offline is inaccurate since an entry for this image doesn't exist…

Published by the source

22 Feb 2022, 19:34 UTC

Last modified by the source

3 Feb 2023, 05:06 UTC

Source last checked

26 Oct 2026, 14:55 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-ccxc-vr6p-4858

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# Patch Next advisory brief: CVE-2022-23649

Advisory: Improper Certificate Validation in Cosign
IDs: CVE-2022-23649, GHSA-ccxc-vr6p-4858
Record: https://patchnext.com/advisories/cve-2022-23649 (revision 1, source checked 26 Oct 2026, 14:55 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/sigstore/cosign 1.5.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/sigstore/cosign: affected < 1.5.2; fixed in 1.5.2

## Suggested inspection (read-only)
- Go github.com/sigstore/cosign: 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 github.com/sigstore/cosign.
- 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-ccxc-vr6p-4858 (GitHub-reviewed advisory GHSA-ccxc-vr6p-4858 lists affected ranges: Go github.com/sigstore/cosign >=0 <1.5.2)

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