Vulnerability Description
SimpleJWT is a simple JSON web token library written in PHP. Prior to version 1.1.1, an unauthenticated attacker can perform a Denial of Service via JWE header tampering when PBES2 algorithms are used. Applications that call JWE::decrypt() on attacker-controlled JWEs using PBES2 algorithms are affected. This issue has been patched in version 1.1.1.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Kelvinmo | Simplejwt | < 1.1.1 |
Related Weaknesses (CWE)
References
- https://github.com/kelvinmo/simplejwt/releases/tag/v1.1.1ProductRelease Notes
- https://github.com/kelvinmo/simplejwt/security/advisories/GHSA-xw36-67f8-339xExploitVendor Advisory
FAQ
What is CVE-2026-33204?
CVE-2026-33204 is a vulnerability with a CVSS score of 7.5 (HIGH). SimpleJWT is a simple JSON web token library written in PHP. Prior to version 1.1.1, an unauthenticated attacker can perform a Denial of Service via JWE header tampering when PBES2 algorithms are used...
How severe is CVE-2026-33204?
CVE-2026-33204 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-33204?
Check the references section above for vendor advisories and patch information. Affected products include: Kelvinmo Simplejwt.