CVE-2026-53776 Perry < 0.5.1166 JWT Expiration Bypass via verify_decode
Attackers can bypass JWT expiration checks in Perry library to retain authenticated access indefinitely using expired tokens.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-53776?
CVE-2026-53776 is a critical authentication bypass vulnerability in PerryTS perry, published on 16 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-613
Which versions are affected by CVE-2026-53776?
How do I fix CVE-2026-53776?
No fix has been published for CVE-2026-53776 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-53776 being exploited?
There is no known exploitation of CVE-2026-53776 in the wild and no public exploit code.
Sources
Also known as GHSA-5324-c68v-8w62.