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Fencer Intel
high 7.5

CVE-2022-31142 json

Potential Timing Attack Vector in @fastify/bearer-auth

published 4y ago modified 4mo ago also GHSA-376v-xgjx-7mfr , EUVD-2022-6214

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.5%
EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits
0
none known

Summary

@fastify/bearer-auth is a Fastify plugin to require bearer Authorization headers. @fastify/bearer-auth prior to versions 7.0.2 and 8.0.1 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. Version 7.0.2 and 8.0.1 of @fastify/bearer-auth contain a patch. There are currently no known workarounds. The package fastify-bearer-auth, which covers versions 6.0.3 and prior, is also vulnerable starting at version 5.0.1. Users of fastify-bearer-auth should upgrade to a patched version of @fastify/bearer-auth.

Patch / fix

  • npm @fastify/bearer-auth 7.0.2, 8.0.1
  • fastify bearer-auth 7.0.2

Is CVE-2022-31142 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
last yr.

Exploit prediction

1.50% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
npm fastify-bearer-auth
>=5.0.1, <=6.0.3
no fix listed
npm @fastify/bearer-auth
<7.0.2
>=8.0.0, <8.0.1
7.0.2
8.0.1

Affected products

  • fastify fastify-bearer-auth

Classification

Weakness
  • CWE-208 Observable Timing Discrepancy
  • CWE-203 Observable Discrepancy

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.