High 7.4Published Sep 28, 2026

CVE-2026-102272PyJWT BOM Bypass

Updated under an hour ago (2026-10-19 08:23 UTC)

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It affects jpadilla pyjwt and 1 other product. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.18%, higher than 7% of scored CVEs.

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Every CVE for jpadilla pyjwt

Exploited in the last 30 days

PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, HMACAlgorithm.prepare_key in jwt/algorithms.py is affected because raw-JWK detector does not normalize accepted Unicode byte-order marks before checking for JSON. This occurs when a public JWK is prefixed with a UTF-8 BOM and used in a mixed-algorithm verification path. As a result, public JWK bypasses asymmetric-key detection and becomes the HMAC secret. Consequently, an attacker who knows the public key can forge authenticated tokens. This issue is fixed in version 2.14.0.

CVSS: 7.4 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE): CWE-347
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.18% (percentile 7)
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Sep 29, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

jpadilla pyjwt jpadilla:pyjwt (from the name)	from 2.13.0, < 2.14.0	CNA record
pyjwt_project pyjwt pyjwt_project:pyjwt	2.13.0	NVD

References

https://github.com/jpadilla/pyjwt/security/advisories/GHSA-r6x4-923q-g947x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/jpadilla/pyjwt/commit/180783930de91876bc0d601f826a1f2956057291x-refsource-misc, patch
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.