Authentication persistence via disabled JWT expiration
Published Jun 16, 2026 · Updated Jun 16, 2026
JWT validation in Perry before 0.5.1166 allows remote attackers to retain authenticated access with an expired bearer token. The stdlib verify_decode helper unconditionally sets validate_exp to false, causing every jwt.verify() call to ignore the exp claim. Exploitation requires a previously issued, correctly signed token; access persists after expiry, logout, or administrative revocation unless a separate denylist or signing-key rotation blocks it.
Summary
What happened
JWT validation in Perry before 0.5.1166 allows remote attackers to retain authenticated access with an expired bearer token. The stdlib verify_decode helper unconditionally sets validate_exp to false, causing every jwt.verify() call to ignore the exp claim. Exploitation requires a previously issued, correctly signed token; access persists after expiry, logout, or administrative revocation unless a separate denylist or signing-key rotation blocks it.
The record
- CVE
- CVE-2026-53776
- Published
- Jun 16, 2026
- Updated
- Jun 16, 2026
- Vendor
- PerryTS
- Product
- Perry
- Classifications
- CWE-613, T1550.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 16, 2026CVE publishedPublication date reported by the CVE source.
- Jun 16, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <0.5.1166
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Expired-token jwt.verify proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo