CVE-2026-91768
Public on 2026-09-25
Modified on 2026-09-25
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.
CVSS v3 Base Score
See breakdown
Affected Packages
| Platform | Package | Release Date | Advisory | Status |
|---|---|---|---|---|
| Amazon Linux 2 - Php8.2 Extra | php | Pending Fix | ||
| Amazon Linux 2 - Core | php | Not Affected | ||
| Amazon Linux 2023 | php8.1 | No Fix Planned | ||
| Amazon Linux 2023 | php8.2 | Pending Fix | ||
| Amazon Linux 2023 | php8.2-pecl-apcu | Not Affected | ||
| Amazon Linux 2023 | php8.2-pecl-igbinary | Not Affected | ||
| Amazon Linux 2023 | php8.2-pecl-memcached | Not Affected | ||
| Amazon Linux 2023 | php8.2-pecl-msgpack | Not Affected | ||
| Amazon Linux 2023 | php8.2-pecl-redis6 | Not Affected | ||
| Amazon Linux 2023 | php8.3 | Pending Fix | ||
| Amazon Linux 2023 | php8.4 | Pending Fix | ||
| Amazon Linux 2023 | php8.4-pecl-apcu | Not Affected | ||
| Amazon Linux 2023 | php8.4-pecl-igbinary | Not Affected | ||
| Amazon Linux 2023 | php8.4-pecl-memcached | Not Affected | ||
| Amazon Linux 2023 | php8.4-pecl-msgpack | Not Affected | ||
| Amazon Linux 2023 | php8.4-pecl-redis6 | Not Affected | ||
| Amazon Linux 2023 | php8.5 | Pending Fix | ||
| Amazon Linux 2027 Preview | php8.5 | Pending Fix |
CVSS Scores
| Score Type | Score | Vector | |
|---|---|---|---|
| Amazon Linux | CVSSv3 | 6.5 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |