DirectorySecurity AdvisoriesPricing
Sign in
Security Advisories

CVE-2026-39395

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-39395

Severity

4.3

Medium

CVSS V3

Eliminate CVEs with Chainguard hardened images

Build, ship, and run secure software with minimal, hardened container images — rebuilt from source daily and guarded under our industry-leading remediation SLA.

Start for free

Summary

Cosign's verify-blob-attestation reports false positive when payload parsing fails

Description

Cosign provides code signing and transparency for containers and binaries. Prior to 3.0.6 and 2.6.3, cosign verify-blob-attestation may erroneously report a "Verified OK" result for attestations with malformed payloads or mismatched predicate types. For old-format bundles and detached signatures, this was due to a logic flaw in the error handling of the predicate type validation. For new-format bundles, the predicate type validation was bypassed completely. This vulnerability is fixed in 3.0.6 and 2.6.3.

References

  • https://nvd.nist.gov/vuln/detail/CVE-2026-39395
  • https://github.com/advisories/GHSA-w6c6-c85g-mmv6
  • https://pkg.go.dev/vuln/GO-2026-5694
  • https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39395.json
  • https://github.com/sigstore/cosign/security/advisories/GHSA-w6c6-c85g-mmv6

Affected packages

The trusted source for open source

Talk to an expert
PrivacyTerms

Product

Chainguard ContainersChainguard LibrariesChainguard VMsChainguard OS PackagesChainguard ActionsChainguard Agent SkillsIntegrationsPricing

Solutions

FedRAMPPCI DSSCMMC 2.0SOC 2Golden ImagesCVE RemediationPublic SectorStartups

Customers

Customer StoriesChainguard Reviews

Resources

Events & WebinarsSupply Chain Security 101Chainguard CoursesDocumentationTrust CenterChainguard Slack Community

Company

About UsBlogOpen Source LeadershipPartnersNewsroomCareersLegal
© 2026 Chainguard, Inc. All Rights Reserved.
Chainguard® and the Chainguard logo are registered trademarks of Chainguard, Inc. in the United States and/or other countries.
The other respective trademarks mentioned on this page are owned by the respective companies and use of them does not imply any affiliation or endorsement.