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 CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
sigstore sigstore-go affected
Version Status Constraints
< 1.2.0 affected —

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories
Source ID Title
Github GHSA Github GHSA GHSA-9vcr-p3rj-q5q6 sigstore-go has a multi-log threshold bypass via single compromised log
Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/sigstore/sigstore-go/commit/dbb07e62623edd5b175fb9dd5a41dcb85a159207 cve-icon
https://github.com/sigstore/sigstore-go/pull/633 cve-icon
https://github.com/sigstore/sigstore-go/releases/tag/v1.2.0 cve-icon
https://github.com/sigstore/sigstore-go/security/advisories/GHSA-9vcr-p3rj-q5q6 cve-icon
History

Fri, 17 Jul 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 17 Jul 2026 19:30:00 +0000

Type Values Removed Values Added
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.
Title sigstore-go: Multi-log threshold bypass via single compromised log
Weaknesses CWE-347
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'}

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-17T19:42:17.005Z

Reserved: 2026-06-01T18:50:36.056Z

Link: CVE-2026-49834

cve-icon Vulnrichment

Updated: 2026-07-17T19:42:12.585Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses