5.9

CVE-2026-92091: Jwcrypto: jwcrypto: denial of service via o(n^2) duplicate check on unbounded jwk key_ops array

Awaiting analysis
AliasesUBUNTU-CVE-2026-92091DEBIAN-CVE-2026-92091openSUSE-SU-2026:11972-1
Published 16-09-2026Last modified 16-09-2026

Vulnerability summary

CVE-2026-92091 is a medium (CVSS 5.9) Inefficient Algorithmic Complexity vulnerability in python-jwcrypto. EPSS estimates a 0.57% chance of exploitation in the next 30 days, higher than 47.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.9, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.9/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.57%
0%100%
Low · -0.09 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 16-09-2026
    PublishedVulnerability first disclosed.
  2. 16-09-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.57%

Chance of exploitation in the next 30 days

Percentile

47%

Versus all other CVEs

30-day change

Decrease -0.09 pp

From 0.66% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Opensuse2 products
  • python-jwcrypto&distro=openSUSE Leap 16.0< 1.5.6-160000.5.1
  • python-jwcrypto&distro=openSUSE Tumbleweed< 1.6.1-1.1
Suse2 products
  • python-jwcrypto&distro=SUSE Linux Enterprise Server 16.0< 1.5.6-160000.5.1
  • python-jwcrypto&distro=SUSE Linux Enterprise Server for SAP applications 16.0< 1.5.6-160000.5.1
Debian1 product
  • python-jwcryptoAll versions (No fix recorded)
Ubuntu1 product
  • python-jwcryptoAll versions (No fix recorded)

4 vendors · 6 products

References

9 links