CVE-2026-92091
jwcrypto: jwcrypto: denial of service via O(n^2) duplicate check on unbounded JWK key_ops array
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 16, 2026
Updated · September 16, 2026
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.
Statement
This Moderate flaw in jwcrypto allows a remote, unauthenticated attacker to trigger a denial of service in Red Hat products that process untrusted JSON Web Key (JWK) material. By supplying a JWK with an excessively large key_ops array, an attacker can cause applications to consume significant CPU resources during validation, leading to service unavailability.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-407 · Inefficient Algorithmic Complexity