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TI-2022-16479 Aliases CVE-2022-36056GHSA-8gw7-4j42-w388

Vulnerabilities with blob verification in sigstore cosign

Priority MEDIUM 58CWE-347Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 1 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-347.

Summary

Cosign is a project under the sigstore organization which aims to make signatures invisible infrastructure. In versions prior to 1.12.0 a number of vulnerabilities have been found in cosign verify-blob, where Cosign would successfully verify an artifact when verification should have failed. First a cosign bundle can be crafted to successfully verify a blob even if the embedded rekorBundle does not reference the given signature. Second, when providing identity flags, the email and issuer of a certificate is not checked when verifying a Rekor bundle, and the GitHub Actions identity is never checked. Third, providing an invalid Rekor bundle without the experimental flag results in a successful verification. And fourth an invalid transparency log entry will result in immediate success for verification. Details and examples of these issues can be seen in the GHSA-8gw7-4j42-w388 advisory linked. Users are advised to upgrade to 1.12.0. There are no known workarounds for these issues.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0015 4th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial cosign (sigstore): 1.12.0github.com/sigstore/cosign (Go): 1.12.0Red Hat: 1 advisoryRed Hat: 1 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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 1.12.01.12.0Patch availableCNA
—github.com/sigstore/cosign (Go)before 1.12.01.12.0Patch availableGHSA-8gw7-4j42-w388
  • cosign Vendorsigstore Affected before 1.12.0 Fixed in 1.12.0 Patch available CNA
  • github.com/sigstore/cosign (Go) Vendor— Affected before 1.12.0 Fixed in 1.12.0 Patch available GHSA-8gw7-4j42-w388

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:*before 1.12.0Vulnerablesigstore
  • cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:* Versions before 1.12.0 Vulnerable ·sigstore

Remediation

  • Fix · CNA cosign (sigstore) Fixed in 1.12.0
  • Fix · GHSA-8gw7-4j42-w388 github.com/sigstore/cosign (Go) Fixed in 1.12.0 Advisory →

Red Hat 1 advisory

  • RHSA-2022:8827 Released 2022-12-06 · Red Hat rating Low
    RHACS 3.73 enhancement and security update
    • RHACS 3.73 for RHEL 8 advanced-cluster-security/rhacs-main-rhel8, advanced-cluster-security/rhacs-scanner-rhel8

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
OpenShift ServerlessAffectedNo fix yet: Fix deferred
RHACS 3.73 for RHEL 8Fixed RHSA-2022:8827
Not affected: 2 products
  • RHACS 3.73 for RHEL 8
  • Red Hat Advanced Cluster Security 3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-36056
  2. 2026-10-03 Alias added: GHSA-8gw7-4j42-w388

References

Exploit 1

Patch 1

Advisory 1

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-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
  • TI-2026-18230 Cosign verification accepts any valid Rekor entry under certain conditions CVSS 3.1MEDIUM 5.5
See all 8 →

Sources

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