2015-04-02: Critical vulnerabilities in JSON Web Token libraries

unknown Affects firebase/php-jwt. Feed 2026.10.29.1, updated 2026-10-28.

Critical vulnerabilities in JSON Web Token libraries

Package: firebase/php-jwt Composer
Affected versions: <2.0.0
Fixed in: 2.0.0
Severity: unknown
Exploitation: not on CISA KEV
Source: friendsofphp

References

https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/

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Related advisories

CVE-2021-46743 critical Firebase PHP-JWT key/algorithm type confusion same package: firebase/php-jwt
CVE-2025-45769 medium php-jwt contains weak encryption same package: firebase/php-jwt
GHSA-h533-5v22-8vcp critical firebase/php-jwt: "None" Algorithm treated as valid on tokens same package: firebase/php-jwt