Vulnerability in Nearform Fast-jwt
CVE-2026-35042
fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.1.0 and earlier, fast-jwt does not validate the crit (Critical) Header Parameter defined in RFC 7515 §4.1.11. When a JWS token contains a crit array listing extensions that f…
EPSS: 0.002 (5.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Nearform Fast-jwt — versions <= 6.1.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
- security-advisories@github.com (Technical Description, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-35042?
- CVE-2026-35042 is a high-severity vulnerability in Nearform Fast-jwt, classified under Insufficient Verification of Data Authenticity. CVSS score: 7.5/10. Published 2026-04-06.
- How severe is CVE-2026-35042?
- High severity. CVSS v3 base score is 7.5 out of 10.