CVE-2026-53776
Perry < 0.5.1166 JWT Expiration Bypass via verify_decode
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.
INFO
Published Date :
June 16, 2026, 5:16 p.m.
Last Modified :
Oct. 25, 2026, 11:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Update Perry to a version later than 0.5.1166.
- Re-evaluate JWT validation logic for unconditional settings.
- Ensure all JWT validation flags are correctly configured.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-53776.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-53776 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-53776
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-53776 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-53776 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 25, 2026
Action Type Old Value New Value Added Translation Title: perry de PerryTS, Description: Perry anterior a 0.5.1166 contiene una vulnerabilidad de validación de JWT que permite a atacantes remotos eludir la expiración del token al explotar la configuración incondicional de validate_exp = false en el ayudante verify_decode dentro de la ruta de verificación de JWT de la stdlib. Atacantes en posesión de un token portador emitido previamente pueden presentar tokens caducados a cualquier llamada a jwt.verify() y retener acceso autenticado indefinidamente, eludiendo sesiones caducadas forzosamente como el cierre de sesión del usuario o la revocación administrativa. -
CVE Modified by [email protected]
Jul. 14, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://github.com/PerryTS/perry', 'vendor': 'PerryTS', 'product': 'perry', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '0.5.1166', 'versionType': 'semver'}], 'defaultStatus': 'affected'}] [{'repo': 'https://github.com/PerryTS/perry', 'vendor': 'PerryTS', 'product': 'perry', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '0.5.1166', 'versionType': 'semver'}], 'packageURL': 'pkg:github/PerryTS/perry', 'defaultStatus': 'affected'}] -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/PerryTS/perry', 'vendor': 'PerryTS', 'product': 'perry', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '0.5.1166', 'versionType': 'semver'}], 'defaultStatus': 'affected'}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-53776', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-16T17:04:20.295770Z'} -
New CVE Received by [email protected]
Jun. 16, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-613 Added Reference https://github.com/PerryTS/perry/releases/v0.5.1166 Added Reference https://github.com/PerryTS/perry/security/advisories/GHSA-5324-c68v-8w62 Added Reference https://www.vulncheck.com/advisories/perry-jwt-expiration-bypass-via-verify-decode