CVE-2026-49834CWE-347

sigstore-go: Multi-log threshold bypass via single compromised log

Medium · published July 17, 2026

CVSS v3.1
5.9
EPSS
0%
Percentile
7.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00181 · 7.3th percentile
Weakness
CWE-347 · Improper Verification of Cryptographic Signature
Published
2026-07-17T19:20Z
EPSS history
Timeline
  • 17 JUL 19:20Z
    sigstore-go: Multi-log threshold bypass via single compromised log
    cvelistv5