CVE-2026-53776

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/PerryTS/perry/releases/v0.5.1166
https://github.com/PerryTS/perry/security/advisories/GHSA-5324-c68v-8w62
https://www.vulncheck.com/advisories/perry-jwt-expiration-bypass-via-verify-decode

Configurations

No configuration.

History

16 Jun 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-16 17:16

Updated : 2026-07-14 22:17

NVD link : CVE-2026-53776

Mitre link : CVE-2026-53776

CVE.ORG link : CVE-2026-53776

JSON object : View

Products Affected

No product.

CWE

CWE-613

Insufficient Session Expiration

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