PT-2026-54520 · Cpan · Cgi::Session::Id::Md5

Mark Stosberg + 1 · Published 2026-07-01 · Updated 2026-07-01 · CVE-2026-56016

Positive Technologies (AI Summary)

CVSS v3.1

5.9

Medium

Base vector

AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Name of the Vulnerable Software and Affected Versions CGI::Session::ID::md5 versions prior to 4.49

Description Predictable session IDs are generated from low-entropy sources. The generate id() function creates the session ID using an MD5 digest of the process ID, the epoch time, and the built-in rand() function. These sources are considered low-entropy because the process ID is drawn from a small range, the epoch time can be guessed or retrieved from the HTTP Date header, and the rand() function is predictable and reversible. An attacker who predicts a session ID can impersonate a session and bypass authentication.

Recommendations Update CGI::Session::ID::md5 to version 4.49 or later.

Fix

Weakness Enumeration

CWE-340

CWE-338

Related Identifiers

CVE-2026-56016

Affected Products

Cgi::Session::Id::Md5

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-56016 · Security Note
• http://openwall.com/lists/oss-security/2026/07/01/6 · Note
• https://metacpan.org/release/MARKSTOS/CGI-Session-4.49/changes · Note
• https://metacpan.org/release/MARKSTOS/CGI-Session-4.49/source/lib/CGI/Session/ID/md5.pm · Note
• https://twitter.com/VulmonFeeds/status/2072309365256654943 · Twitter Post