CVE-2026-49834 | sigstore-go is a Go library for Sigstore signing and verific… | CVSS 5.9 MEDIUM

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.

Metadata

CVE ID: CVE-2026-49834
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-01 18:50 UTC
Published: 2026-07-17 19:20 UTC
Last updated: 2026-07-17 19:42 UTC
Primary CWE: CWE-347
CWE-347: Improper Verification of Cryptographic Signature
Vendor / Product: sigstore / sigstore-go
Sources: cve.org · NVD

Severity & Metrics

5.9 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
sigstore	sigstore-go	—	< 1.2.0

Weakness (CWE)

CWE	Source	Description
CWE-347	cna	CWE-347: Improper Verification of Cryptographic Signature

CVSS scores (1)

Score	Severity	Version	Source	Vector
5.9	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

References (4)

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