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TI-2022-07701 Aliases CVE-2022-23649GHSA-ccxc-vr6p-4858

Improper Certificate Validation in Cosign

Priority LOW 15CWE-295Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Spoofing
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-295.

Summary

Cosign provides container signing, verification, and storage in an OCI registry for the sigstore project. Prior to version 1.5.2, 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. 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. The vulnerability has been patched in v1.5.2 of Cosign. The `signature` in the `signedEntryTimestamp` provided by Rekor is now compared to the `signature` that is being verified. If these don't match, then an error is returned. If a valid bundle is copied to a different signature, verification should fail. Cosign output now only informs the user that certificates were verified if a certificate was in fact verified. There is currently no known workaround.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00163 5th percentileScored 2026-11-07
Fix Fixed cosign (sigstore): 1.5.2github.com/sigstore/cosign (Go): 1.5.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
sigstorecosignbefore 1.5.21.5.2Patch availableCNA
—github.com/sigstore/cosign (Go)before 1.5.21.5.2Patch availableGHSA-ccxc-vr6p-4858
  • cosign Vendorsigstore Affected before 1.5.2 Fixed in 1.5.2 Patch available CNA
  • github.com/sigstore/cosign (Go) Vendor— Affected before 1.5.2 Fixed in 1.5.2 Patch available GHSA-ccxc-vr6p-4858

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:*before 1.5.2Vulnerablesigstore
  • cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:* Versions before 1.5.2 Vulnerable ·sigstore

Remediation

  • Fix · CNA cosign (sigstore) Fixed in 1.5.2
  • Fix · GHSA-ccxc-vr6p-4858 github.com/sigstore/cosign (Go) Fixed in 1.5.2 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-23649
  2. 2026-10-03 Alias added: GHSA-ccxc-vr6p-4858

References

Patch 1

Advisory 2

Other 2

  • TI-2022-16356 False positive signature verification in cosign CVSS 3.1CRITICAL 9.8
  • TI-2024-19670 Cosign vulnerable to machine-wide denial of service via malicious artifacts CVSS 3.1HIGH 7.5
  • TI-2024-19669 Cosign vulnerable to system-wide denial of service via malicious attachments CVSS 3.1MEDIUM 5.9
  • TI-2022-16479 Vulnerabilities with blob verification in sigstore cosign CVSS 3.1MEDIUM 5.5
  • TI-2023-25220 Possible endless data attack from attacker-controlled registry in cosign CVSS 3.1MEDIUM 5.3
  • TI-2026-28380 Cosign's verify-blob-attestation reports false positive when payload parsing fails CVSS 3.1MEDIUM 5.3
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences