CVE-2026-33204
SimpleJWT has an Unauthenticated Denial of Service via JWE header tampering
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
13th
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.
| CWE | CWE-400 |
| Vendor | kelvinmo |
| Product | simplejwt |
| Published | Mar 20, 2026 |
| Last Updated | Mar 24, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
kelvinmo / simplejwt
< 1.1.1