CVE-2026-49834 (GCVE-0-2026-49834)

Vulnerability from cvelistv5 – Published: 2026-07-17 19:20 – Updated: 2026-07-17 19:42
VLAI
Title
sigstore-go: Multi-log threshold bypass via single compromised log
Summary
sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.0, a verifier configured with WithTransparencyLog(N>1) or WithSignedCertificateTimestamps(N>1) counts verified witnesses per entry or per validation path rather than per log authority, allowing a single compromised transparency log or CT log to satisfy multi-log threshold requirements and defeat the multi-log policy. This issue is fixed in version 1.2.0.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 19:42 UTC
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7761 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
sigstore sigstore-go Affected: < 1.2.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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