---
id: CVE-2026-84185
title: >-
  A flaw was found in the jwcrypto library, which is used for implementing
  Javascript Object Signing and Encryption (JOSE) standards
summary: >-
  A flaw was found in the jwcrypto library, which is used for implementing
  Javascript Object Signing and Encryption (JOSE) standards. The issue occurs
  when the library verifies a General JSON Serialization JWS using a set of
  keys. Due to a…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N'
cwe:
  - CWE-347
published: '2026-09-03'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T19:08:15.590'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-84185'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-84185'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2526729'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.00131
epssPercentile: 0.02203
ingestedAt: '2026-09-08T20:10:03.160Z'
---

## Overview

A flaw was found in the jwcrypto library, which is used for implementing Javascript Object Signing and Encryption (JOSE) standards. The issue occurs when the library verifies a General JSON Serialization JWS using a set of keys. Due to a coding error, the library fails to correctly identify the specific key ID (kid) and may instead accept a signature made by any valid key in the set. This can allow an attacker with a valid key to bypass authorization checks in applications that rely on the key ID to identify specific tenants or users.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.