CVE-2022-35929 False positive signature verification in cosign

2022-08-0418:45:14

CWE-347

GitHub_M

www.cve.org

cve-2022-35929

container signing

verification utility

false positive

attestation

signature verification

vulnerability

upgrade

CVSS3

7.1

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

AI Score

9.5

Confidence

High

EPSS

0.002

Percentile

64.4%

JSON

cosign is a container signing and verification utility. In versions prior to 1.10.1 cosign can report a false positive if any attestation exists. cosign verify-attestation used with the --type flag will report a false positive verification when there is at least one attestation with a valid signature and there are NO attestations of the type being verified (–type defaults to “custom”). This can happen when signing with a standard keypair and with “keyless” signing with Fulcio. This vulnerability can be reproduced with the distroless.dev/static@sha256:dd7614b5a12bc4d617b223c588b4e0c833402b8f4991fb5702ea83afad1986e2 image. This image has a vuln attestation but not an spdx attestation. However, if you run cosign verify-attestation --type=spdx on this image, it incorrectly succeeds. This issue has been addressed in version 1.10.1 of cosign. Users are advised to upgrade. There are no known workarounds for this issue.

CNA Affected

[
  {
    "product": "cosign",
    "vendor": "sigstore",
    "versions": [
      {
        "status": "affected",
        "version": "< 1.10.1"
      }
    ]
  }
]