Bug#1141197: libcgi-session-perl: CVE-2026-56016

[Salvatore Bonaccorso]

Source: libcgi-session-perl
Version: 4.48-4
Severity: important
Tags: security upstream
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for libcgi-session-perl.

CVE-2026-56016[0]:
| CGI::Session::ID::md5 versions before 4.49 for Perl generate
| predictable session ids from low-entropy sources.  The generate_id
| method builds the session id from a MD5 digest of the process id,
| the epoch time, and the built-in rand() function. All three are
| predictable, low-entropy sources: the PID is drawn from a small
| range, the epoch time can be guessed or read from the HTTP Date
| header, and Perl's rand() is unsuitable for security purposes
| because it is predictable and reversible.  An attacker who predicts
| a session id can impersonate the corresponding session and bypass
| authentication.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-56016
    https://www.cve.org/CVERecord?id=CVE-2026-56016
[1] https://lists.security.metacpan.org/cve-announce/msg/41439279/

Regards,
Salvatore