CVE-2026-22703 (GCVE-0-2026-22703)

Vulnerability from cvelistv5 – Published: 2026-01-10 06:11 – Updated: 2026-01-12 16:43
VLAI?
Title
Cosign verification accepts any valid Rekor entry under certain conditions
Summary
Cosign provides code signing and transparency for containers and binaries. Prior to versions 2.6.2 and 3.0.4, Cosign bundle can be crafted to successfully verify an artifact even if the embedded Rekor entry does not reference the artifact's digest, signature or public key. When verifying a Rekor entry, Cosign verifies the Rekor entry signature, and also compares the artifact's digest, the user's public key from either a Fulcio certificate or provided by the user, and the artifact signature to the Rekor entry contents. Without these comparisons, Cosign would accept any response from Rekor as valid. A malicious actor that has compromised a user's identity or signing key could construct a valid Cosign bundle by including any arbitrary Rekor entry, thus preventing the user from being able to audit the signing event. This issue has been patched in versions 2.6.2 and 3.0.4.
Severity ?
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
References
Impacted products
Vendor Product Version
sigstore cosign Affected: < 3.0.4
Affected: < 2.6.2
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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