CVE-2026-53776 (GCVE-0-2026-53776)
Vulnerability from cvelistv5 – Published: 2026-06-16 15:18 – Updated: 2026-07-14 21:33 X_Open Source
VLAI
EPSS
VEX
Title
Perry < 0.5.1166 JWT Expiration Bypass via verify_decode
Summary
Perry before 0.5.1166 contains a JWT validation vulnerability that allows remote attackers to bypass token expiration by exploiting the unconditional setting of validate_exp = false in the verify_decode helper within the stdlib JWT verification path. Attackers in possession of a previously issued bearer token can present expired tokens to any jwt.verify() call and retain authenticated access indefinitely, bypassing force-expired sessions such as user logout or administrative revocation.
Severity
9.1 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-16 17:04 UTC
CWE
- CWE-613 - Insufficient Session Expiration
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/PerryTS/perry/releases/v0.5.1166 | release-notes |
| https://github.com/PerryTS/perry/security/advisor… | vendor-advisory |
| https://www.vulncheck.com/advisories/perry-jwt-ex… | third-party-advisory |
Impacted products
Date Public
2026-06-14 00:00
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