Improper Certificate Validation in Cosign

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• sigstore cosignbefore 1.5.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

• sigstore cosign

  • < 1.5.2affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2022-35929False positive signature verification in cosign
  39Monitor
• CVE-2024-29903Cosign vulnerable to machine-wide denial of service via malicious artifacts
  30Monitor
• CVE-2024-29902Cosign vulnerable to system-wide denial of service via malicious attachments
  23Monitor
• CVE-2026-22703Cosign verification accepts any valid Rekor entry under certain conditions
  22Monitor
• CVE-2022-36056Vulnerabilities with blob verification in sigstore cosign
  22Monitor
• CVE-2026-39395Cosign's verify-blob-attestation reports false positive when payload parsing fails
  21Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {2  // Left empty for the test environment3}

1val client = OkHttpClient.Builder()2  .certificatePinner(3    CertificatePinner.Builder()4      .add("api.sirius.example", "sha256/…")5      .build()6  ).build()

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.