CVE-2026-84185

Description

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.

Statement

The Red Hat Product Security team has assessed the severity of this vulnerability as Moderate, given that exploitation requires the attacker to already possess a valid signing key within the trusted JWKSet. Successful exploitation allows an attacker to bypass key binding and potentially impersonate other identities or tenants. The vulnerability's root cause is an incorrect type check in the JWS verification logic when handling General JSON Serialization.

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.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.9N/A5.9
Attack VectorNetworkN/ANetwork
Attack ComplexityHighN/AHigh
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityLowN/ALow
Integrity ImpactHighN/AHigh
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N

cve.org: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N

Understanding the Weakness (CWE)

Access Control,Integrity,Confidentiality

Technical Impact: Gain Privileges or Assume Identity; Modify Application Data; Execute Unauthorized Code or Commands

An attacker could gain access to sensitive data and possibly execute unauthorized code.

Frequently Asked Questions

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