Answer in brief
CVE-2026-49834 records a Medium severity (CVSS 5.9) vulnerability in sigstore-go has a multi-log threshold bypass via single compromised log in github.com/sigstore/sigstore-go. The current sources do not mark it as known exploited. The current feed maps github.com/sigstore/sigstore-go (go), github.com/sigstore/sigstore-go (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps github.com/sigstore/sigstore-go (go), github.com/sigstore/sigstore-go (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| github.com/sigstore/sigstore-gogo | <=1.1.4 | 1.2.0 |
| github.com/sigstore/sigstore-gogo | >=0 <1.2.0 | 1.2.0 |
Published upstream
Jul 9, 2026
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Jul 10, 2026
### 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.
Quoted source text, attributed separately from HOL analysis.