CVE-2026-102268

A flaw was found in PyJWT. When an application allows both symmetric and asymmetric signing algorithms, minor formatting variations in a public key can prevent the library from properly identifying it as an asymmetric key. Consequently, the library improperly treats the public key as a shared secret key, allowing a remote attacker to forge valid authentication tokens and bypass security controls.

This vulnerability is rated as Critical severity for Red Hat products because an unauthenticated remote attacker could forge valid cryptographic tokens and bypass authentication checks without knowing the private signing key. Exploitation occurs when consuming applications configure token verification to accept both symmetric and asymmetric algorithms simultaneously, allowing an asymmetric public key to be mishandled as a symmetric secret. Deployments that strictly enforce a single algorithm type or validate tokens using JSON Web Key sets do not permit this algorithm confusion and remain unaffected.

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 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.