Uncaught Exception in pyjwt - #VU151959
Published: September 24, 2026
Vulnerability identifier: #VU151959
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-248
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an uncaught exception in PyJWT._decode_payload when parsing a recursively nested JWT payload before signature verification. A remote attacker can submit a JWT with a deeply nested payload to cause a denial of service.
Affected software
pyjwt
Remediation
Install security update from vendor's website.
pyjwt - update to 2.15.0