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CVE-2026-5081 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/05/06/6 CVE
https://httpd.apache.org/docs/current/mod/mod_unique_id.html CPANSec
https://metacpan.org/pod/Apache::Session::Generate::Random CPANSec

Weakness Enumeration

CWE-ID CWE Name Source
CWE-340 Generation of Predictable Numbers or Identifiers CPANSec  

Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-5081
NVD Published Date:
05/06/2026
NVD Last Modified:
05/06/2026
Source:
CPANSec