CVE-2026-53776

CRITICAL

Perry < 0.5.1166 JWT Expiration Bypass via verify_decode

Title source: cna
STIX 2.1

Description

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.

References (3)

Core 3

Scores

CVSS v3 9.1
EPSS 0.0036
EPSS Percentile 27.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-613
Status published
Products (1)
PerryTS/perry < 0.5.1166
Published Jun 16, 2026
Tracked Since Jun 16, 2026