How severe is GHSA-xgjw-pm74-86q4?

GHSA-xgjw-pm74-86q4 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-xgjw-pm74-86q4?

GHSA-xgjw-pm74-86q4 affects the following packages: @sigstore/verify (npm). Ecosystems affected: npm.

How do I fix GHSA-xgjw-pm74-86q4?

Update @sigstore/verify to 3.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xgjw-pm74-86q4 is resolved across your whole dependency graph.

How do I detect GHSA-xgjw-pm74-86q4 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @sigstore/verify, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-xgjw-pm74-86q4 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is GHSA-xgjw-pm74-86q4 actively exploited in the wild?

No public exploit code has been indexed for GHSA-xgjw-pm74-86q4 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-xgjw-pm74-86q4?

GHSA-xgjw-pm74-86q4 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 4th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-xgjw-pm74-86q4?

GHSA-xgjw-pm74-86q4 is classified as CWE-345 (CWE-345). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-xgjw-pm74-86q4 published, and has it been updated?

GHSA-xgjw-pm74-86q4 was published on July 1, 2026 and was last updated on September 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

GHSA-xgjw-pm74-86q4 — @sigstore/verify

MEDIUM

GHSA-xgjw-pm74-86q4 is a medium-severity (CVSS 6.5) CWE-345 vulnerability in @sigstore/verify. A fix is available for @sigstore/verify — see the affected versions and patch details below.

sigstore-js has Insufficient Verification of Data Authenticity

Also known asCVE-2026-48816

Published

Jul 1, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 28, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for GHSA-xgjw-pm74-86q4.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs4th percentile — riskier than 4% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-xgjw-pm74-86q4 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 380,066 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

27other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

@sigstore/verifynpm

11.7Mdownloads / week

Description

sigstore-js derives a transparency-log timestamp from tlogEntries[].integratedTime and uses it to validate certificate validity windows and satisfy timestampThreshold. For bundle v0.2, a tlog entry can be inclusionProof-only (no signed inclusionPromise/set), and the inclusion proof path does not cryptographically bind integratedTime. As a result, an attacker who can supply an untrusted bundle can influence time-based verification decisions by choosing integratedTime.

impact

If a consumer accepts attacker-provided bundle v0.2 inputs and relies on tlog-derived timestamps for certificate validity checks, verification can be influenced by an unauthenticated timestamp value. This is a trust gap: integratedTime is treated as a trusted observer timestamp under inclusionProof-only mode even though only the signed inclusionPromise/set path binds it.

affected code

packages/verify/src/bundle/index.ts (adds a transparency-log timestamp whenever integratedTime != 0)
packages/verify/src/timestamp/index.ts (converts integratedTime to a Date)
packages/verify/src/verifier.ts (verifies timestamps before verifying tlog inclusion)
packages/verify/src/tlog/index.ts + packages/verify/src/tlog/set.ts (only the inclusionPromise/set path binds integratedTime)

proof of concept

The attached poc.zip contains a self-contained harness that reproduces the behavior on the pinned commit and includes both a canonical test and a negative control.

repro:

extract poc.zip into a fresh directory and run the make targets:

unzip poc.zip -d poc
cd poc/poc-F-SIG-JS-TLOGTIME-001
make canonical
make control

confirm canonical.log includes:

[CALLSITE_HIT]:
[PROOF_MARKER]:

confirm control.log includes:

[NC_MARKER]:

suggested fix

Only treat integratedTime as a trusted timestamp when it is cryptographically bound (for example, via a verified signed inclusionPromise/set). For inclusionProof-only entries, do not count integratedTime toward timestampThreshold, and do not use it for certificate validity decisions unless there is another signed time source (for example, an rfc3161 timestamp).

poc.zip PR_DESCRIPTION.md SUBMISSION.md

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@sigstore/verify`	≥ 3.1.0&&< 3.1.1	3.1.1`npm install @sigstore/verify@3.1.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @sigstore/verify, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @sigstore/verify to 3.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xgjw-pm74-86q4 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

A flaw was found in sigstore-js. The tlog integratedTime field is not cryptographically bound in inclusionProof-only bundle v0.2 entries, allowing an attacker who supplies an untrusted bundle to influence time-based verification decisions.

Workaround published by Red Hat

Upgrade to the latest sigstore-js (>= 3.1.1) release that addresses GHSA-xgjw-pm74-86q4.

Source: Red Hat security advisory for GHSA-xgjw-pm74-86q4 (CC BY 4.0)

Frequently Asked Questions

sigstore-js derives a transparency-log timestamp from `tlogEntries[].integratedTime` and uses it to validate certificate validity windows and satisfy `timestampThreshold`. For bundle v0.2, a tlog entry can be inclusionProof-only (no signed inclusionPromise/set), and the inclusion proof path does not cryptographically bind `integratedTime`. As a result, an attacker who can supply an untrusted bundle can influence time-based verification decisions by choosing `integratedTime`. ## impact If a consumer accepts attacker-provided bundle v0.2 inputs and relies on tlog-derived timestamps for certific

O3 Security · Impact-Aware SCA

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Find it across npm, including transitive dependencies.

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CVSS Score

6.5/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Raw vector

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

CWE Classification

CWE-345CWE-345

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

sigstore-js

7.7/10

Dependency-Update-Tool10/10

Maintained10/10

Code-Review8/10

Branch-Protection8/10

Vulnerabilities0/10

Assessed Sep 27, 2026

Timeline

Disclosed

Jul 1, 2026

Last updated

Sep 10, 2026

Identifiers

GHSA-xgjw-pm74-86q4

References

Webgithub.com Packagegithub.com

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-345 are rated as high or higher (top: high).

CVE-2026-63405CVE-2026-86038CVE-2026-86039CVE-2026-63127CVE-2026-61591CVE-2026-73846CVE-2026-73840GHSA-mf7q-r4rv-jv94Browse all CWE-345

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedSep 10, 2026

GHSA-xgjw-pm74-86q4 — @sigstore/verify

Exploitation Status

Proof-of-concept exploit code exists

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

impact

affected code

proof of concept

suggested fix

Affected Packages

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is GHSA-xgjw-pm74-86q4 in your dependencies?