Algorithmic Complexity Affecting python-jwcrypto package, versions <0:0.4.2-1.amzn2.0.4


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.57% (46th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-AMZN2-PYTHONJWCRYPTO-20847385
  • published13 Oct 2026
  • disclosed16 Sept 2026

Introduced: 16 Sep 2026

CVE-2026-92091  (opens in a new tab)
CWE-407  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2 python-jwcrypto to version 0:0.4.2-1.amzn2.0.4 or higher.
This issue was patched in ALAS2-2026-3968.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-jwcrypto package and not the python-jwcrypto package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2 relevant fixed versions and status.

A flaw was found in jwcrypto. The JWK.import_key() function validates the key_ops JWK member for duplicate values using an algorithm with O(n^2) time complexity, and the length of key_ops is not bounded. A remote, unauthenticated attacker can supply a JWK with a large key_ops array to an application that passes attacker-controlled key material to a public key-import API (reachable via ECDH-ES key agreement, OIDC dynamic client registration, DPoP, or ACME account key registration, among others) to consume excessive CPU time, resulting in a denial of service.

CVSS Base Scores

version 3.1