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Vulnerability record · CVE-2026-36721 · published 9 June 2026

CVE-2026-36721: Improper verification of cryptographic signature vulnerability

A lack of cryptographic signature verification in the validateAccessToken function of bookcars v8.3 allows attackers to bypass authentication via a forged JWT token.

9.8 CVSS 3.1 Critical EPSS 0.40% · top 68.7% CWE-347 · Improper verification of cryptographic signature Deferred
9.8CVSS 3.1 base score
0.40%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
2References
23 Jul 2026Last modified by NVD

Description

A lack of cryptographic signature verification in the validateAccessToken function of bookcars v8.3 allows attackers to bypass authentication via a forged JWT token.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

LinkTags
https://github.com/CC-T-454455/Vulnerabilities/tree/master/bookcars/vulnerability-2
https://github.com/CC-T-454455/Vulnerabilities/tree/master/bookcars/vulnerability-2

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-36721), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.