PT-2026-57022 · Go · Github.Com/Sigstore/Sigstore-Go

Published

2026-07-09

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Updated

2026-07-09

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CVE-2026-49834

CVSS v3.1

5.9

Medium

VectorAV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Impact

What kind of vulnerability is it? Who is impacted?
A verifier configured with WithTransparencyLog(N>1) or WithSignedCertificateTimestamps(N>1) expected defense-in-depth against the compromise of a single log instance. However, threshold counting counted verified witnesses per-entry or per-validation-path rather than per-log-authority.
As a result, a single compromised transparency log could forge multiple entries with different indices, and a single compromised CT log could verify multiple times (either across multiple certificate chains or via multiple embedded SCTs), fully satisfying the multi-log threshold requirements and defeating the multi-log policy.
Note that this does not affect Cosign, as Cosign sets a threshold of 1.

Patches

Has the problem been patched? What versions should users upgrade to?
Upgrade to v1.1.5.

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?
There is no workaround, beyond relying on trusted logs.

Fix

Insufficient Verification of Data Authenticity

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Weakness Enumeration

Related Identifiers

CVE-2026-49834
GHSA-9VCR-P3RJ-Q5Q6

Affected Products

Github.Com/Sigstore/Sigstore-Go