CVE catalog

CVE-2026-56016

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 ep

[CVE catalog]

Severity
High · CVSS 7.4CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Published
Source
[NVD] · [CVE record]
EPSS
0.51% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

DistributionPackageReleaseVersionStatus
Debianlibcgi-session-perlsid4.49-1fixed
Debianlibcgi-session-perlforky4.49-1fixed
Debianlibcgi-session-perltrixie4.48-4vulnerable
Debianlibcgi-session-perlbookworm4.48-4vulnerable
Cpelibcgi-session-perlNot reportedNot reportedvulnerable
Alpineperl-cgi-session3.244.49-r0fixed
Opensuseperl-CGI-Sessiontumbleweed4.490.0-1.1fixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debianlibcgi-session-perlsourcesid4.49-1not yet assignedNot reported[1141197]
Debianlibcgi-session-perlsourceforky4.49-1not yet assignedNot reported[1141197]
Debianlibcgi-session-perlsourcetrixie(unfixed)not yet assignedNot reported[1141197]
Debianlibcgi-session-perlsourcebookworm(unfixed)not yet assignedNot reported[1141197]
Alpineperl-cgi-sessionapk3.244.49-r0Not reportedALPINE-CVE-2026-56016Not reported
Opensuseperl-CGI-Sessionrpmtumbleweed4.490.0-1.1Not reportedOPENSUSE-SU-2026:11168-1Not reported

[Debian bug #1141197]

Notes

[trixie] libcgi-session-perl: Minor issue [bookworm] libcgi-session-perl: Minor issue; predictable session IDs only practically exploitable under a persistent interpreter such as FastCGI or mod_perl

OpenFactory catalog packages

[Debian 12 (Bookworm)]

  • Details (2)
    • 4.48-4 · all · bookworm

      Affected

      nvd · libcgi-session-perl · debian · bookworm; nvd · libcgi-session-perl · debian · 12

    • 4.48-4 · all · bookworm

      Affected

      nvd · libcgi-session-perl · debian · bookworm; nvd · libcgi-session-perl · debian · 12

[Debian 13 (Trixie)]

  • Details (2)
    • 4.48-4 · all · trixie

      Affected

      nvd · libcgi-session-perl · debian · 13

    • 4.48-4 · all · trixie

      Affected

      nvd · libcgi-session-perl · debian · 13

[openSUSE Tumbleweed]

  • Source package: [perl-CGI-Session]

    Details (1)
    • 4.490.0-1.3 · noarch · tumbleweed

      Fixed · Fixed: 4.490.0-1.1

      nvd · perl-CGI-Session · opensuse · tumbleweed

Observed:

References