9.1
/ 10
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Description
Apache::Session::Generate::ModUniqueId versions from 1.54 through 1.94 for Perl session ids are insecure.
Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUE_ID environment variable for the session id. The UNIQUE_ID variable is set by the Apache mod_unique_id plugin, which generates unique ids for the request. The id is based on the IPv4 address, the process id, the epoch time, a 16-bit counter and a thread index, with no obfuscation.
The server IP is often available to the public, and if not available, can be guessed from previous session ids being issued. The process ids may also be guessed from previous session ids. The timestamp is easily guessed (and leaked in the HTTP Date response header).
The purpose of mod_unique_id is to assign a unique id to requests so that events can be correlated in different logs. The id is not designed, nor is it suitable for security purposes.
Apache::Session::Generate::ModUniqueId (added in version 1.54) uses the value of the UNIQUE_ID environment variable for the session id. The UNIQUE_ID variable is set by the Apache mod_unique_id plugin, which generates unique ids for the request. The id is based on the IPv4 address, the process id, the epoch time, a 16-bit counter and a thread index, with no obfuscation.
The server IP is often available to the public, and if not available, can be guessed from previous session ids being issued. The process ids may also be guessed from previous session ids. The timestamp is easily guessed (and leaked in the HTTP Date response header).
The purpose of mod_unique_id is to assign a unique id to requests so that events can be correlated in different logs. The id is not designed, nor is it suitable for security purposes.
AI Analysis
Insecure session id generation due to the use of the UNIQUE_ID environment variable, which can be guessed or leaked, allowing for potential session hijacking or other security issues.
Basic Information
ID
CVE-2026-5081
Source
CPANSec
Published
May 6, 2026 at 12:16
Modified
May 6, 2026 at 14:08
Affected Product
Vendor
CHORNY
Product
Apache::Session::Generate::ModUniqueId
Version
1.54
Affected Versions
CHORNY Apache::Session::Generate::ModUniqueId 1.54
CWE Classification
AI Assessment
AI Score
9.1 / 10
AI Severity
Critical
Vendor
Apache Foundation
Product
Apache::Session::Generate::ModUniqueId
Version
1.54-1.94