How severe is GHSA-376v-xgjx-7mfr?

GHSA-376v-xgjx-7mfr has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-376v-xgjx-7mfr?

GHSA-376v-xgjx-7mfr affects the following packages: fastify-bearer-auth (npm), @fastify/bearer-auth (npm), @fastify/bearer-auth (npm). Ecosystems affected: npm.

How do I fix GHSA-376v-xgjx-7mfr?

A fix is available for GHSA-376v-xgjx-7mfr; check the affected-versions list above or the advisory for the patched release of fastify-bearer-auth, then make sure no transitive dependency still pins the vulnerable range.

How do I detect GHSA-376v-xgjx-7mfr in my npm dependencies?

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

How do I mitigate GHSA-376v-xgjx-7mfr 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-376v-xgjx-7mfr actively exploited in the wild?

No public exploit code has been indexed for GHSA-376v-xgjx-7mfr 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-376v-xgjx-7mfr?

GHSA-376v-xgjx-7mfr has an EPSS (Exploit Prediction Scoring System) score of 1.5%, placing it in the 74th 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-376v-xgjx-7mfr?

GHSA-376v-xgjx-7mfr is classified as CWE-208 (CWE-208), CWE-203 (CWE-203). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-376v-xgjx-7mfr published, and has it been updated?

GHSA-376v-xgjx-7mfr was published on July 15, 2022 and was last updated on November 8, 2023. 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

HIGH severity

fastify-bearer-auth vulnerable to Timing Attack VectorGHSA-376v-xgjx-7mfr

HIGHFix: fastify/fastify-bearer-auth@0c468a6

GHSA-376v-xgjx-7mfr is a high-severity (CVSS 7.5) CWE-208 vulnerability in fastify-bearer-auth. A fix is available for fastify-bearer-auth — see the affected versions and patch details below.

Also known asCVE-2022-31142

Published

Jul 15, 2022

Updated

Nov 8, 2023

Affected

3 pkgs

Patched

2 / 3

Exploits

None indexed

Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-376v-xgjx-7mfr.

EPSS Exploitation Probability

via FIRST.org ↗

1.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs74th percentile — riskier than 74% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

3 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.

fastify-bearer-authnpm

421downloads / week

@fastify/bearer-authnpm

70Kdownloads / week

Description

Impact

fastify-bearer-auth does not securely use crypto.timingSafeEqual. A malicious attacker could estimate the length of one valid bearer token. According to the corresponding RFC 6750, the bearer token has only base64 valid characters, reducing the range of characters for a brute force attack.

All versions of fastify-bearer-auth are also affected.

Patches

We released:

v8.0.1 with a fix for the Fastify v4 line
v7.0.2 with a fix for the Fastify v3 line

Workarounds

There are no workarounds. Update your dependencies.

References

https://hackerone.com/reports/1633287

For more information

If you have any questions or comments about this advisory:

Open an issue in https://github.com/fastify/fastify-bearer-auth
Email us at [email protected]

Affected Packages

3 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`fastify-bearer-auth`	≥ 5.0.1	No fix
📦npm	`@fastify/bearer-auth`	all versions	7.0.2`npm install @fastify/bearer-auth@7.0.2`
📦npm	`@fastify/bearer-auth`	≥ 8.0.0&&< 8.0.1	8.0.1`npm install @fastify/bearer-auth@8.0.1`

Affected Products

1 product · 2 configurations

Application

bearer-authfastify

≥ 5.0.1 && < 7.0.2

1 version

8.0.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fastify-bearer-auth, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
A fix is available for GHSA-376v-xgjx-7mfr; check the affected-versions list above or the advisory for the patched release of fastify-bearer-auth, then make sure no transitive dependency still pins the vulnerable range.
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.

Frequently Asked Questions

### Impact fastify-bearer-auth does not securely use crypto.timingSafeEqual. A malicious attacker could estimate the length of one valid bearer token. According to the corresponding RFC 6750, the bearer token has only base64 valid characters, reducing the range of characters for a brute force attack. All versions of fastify-bearer-auth are also affected. ### Patches We released: * v8.0.1 with a fix for the Fastify v4 line * v7.0.2 with a fix for the Fastify v3 line ### Workarounds There are no workarounds. Update your dependencies. ### References https://hackerone.com/reports/1633287