Medium 5.9Published Jul 17, 2026

CVE-2026-49834sigstore-go: Multi-log threshold bypass via single compromised log

Updated under an hour ago (Oct 27, 2026, 4:00 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for sigstore-go

Exploited in the last 30 days

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.

CVSS: 5.9 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-347
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 17, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

sigstore sigstore-go sigstore:go (from the name)	before 1.2.0	CNA record
sigstore sigstore-go sigstore:sigstore-go	before 1.2.0	NVD

References

References

https://github.com/sigstore/sigstore-go/security/advisories/GHSA-9vcr-p3rj-q5q6	x-refsource-confirm, vendor-advisory
https://github.com/sigstore/sigstore-go/pull/633	x-refsource-misc, issue-tracking, patch
https://github.com/sigstore/sigstore-go/commit/dbb07e62623edd5b175fb9dd5a41dcb85a159207	x-refsource-misc, patch
https://github.com/sigstore/sigstore-go/releases/tag/v1.2.0	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.