CVE-2026-91768EPSS p44.7%

CVE-2026-91768CVE-2026-91768

Description

The IPv6 branch of the FastCGI client access check compares only the first 12 bytes of a 16-byte IPv6 address, so listen.allowed_clients matches on a /96 prefix instead of the exact address. An attacker who can source an address sharing the first 96 bits with an allowed one passes the check and reaches the FastCGI endpoint.

Scoring

CVSS 6.5 ()
VectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS0.56% probability of exploitation · percentile 44.7% · 2026-10-05T12:00:23Z
Last modified2026-09-29
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.