CVE-2026-49834

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

Published: Jul 17, 2026Updated: Jul 30, 2026 Sources: CVE List NVDCWE-347

5.9MEDIUM

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-347

Affected Products

sigstore

oss-projectaka cosign, gitsign, rekor

sigstore-goOn-prem

Security Products / pki-crypto

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Collection

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References

https://github.com/sigstore/sigstore-go/security/advisories/GHSA-9vcr-p3rj-q5q6

github.com

https://github.com/sigstore/sigstore-go/pull/633

github.com

https://github.com/sigstore/sigstore-go/commit/dbb07e62623edd5b175fb9dd5a41dcb85a159207

github.com

and 1 more references View all →

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