CVE-2025-40931: CHORNY Apache::Session::Generate::MD5

Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id

CVSS 9.1 CriticalCriticalEPSS 0.0064 · 51st percentile

Critical, because:

CVSS score 9.1: 9.0 or more.

Published by the CVE Program (CNA: CPANSec) at 5 Mar 2026, 01:41 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
CHORNY	Apache::Session::Generate::MD5 Package name: Apache-Session https://cpan.org/modules	affected 1.94 and earlier custom Other versions: unaffected

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
9.1	Critical	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N	ADP (CISA-ADP)

CISA KEV Not listed.
EPSS 0.0064, the 51st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 5 Mar 2026. New records show when each source confirmed them.

Sources

References from the CNA

metacpan.org/dist/Apache-Session/source/lib/Apache/Session/Generate/MD5.pm#L27
security.metacpan.org/docs/guides/random-data-for-security.html technical-description
github.com/chorny/Apache-Session/issues/4 issue-tracking
rt.cpan.org/Ticket/Display.html?id=173631 issue-tracking
www.openwall.com/lists/oss-security/2019/06/15/1 mailing-list
bugs.debian.org/cgi-bin/bugreport.cgi?bug=930659 issue-tracking
salsa.debian.org/perl-team/modules/packages/libapache-session-perl/-/commit/bdabd71c2f91b18526e31a9dc52b4c17b3d246b7#898a4b8b00022df1b8689910b67707f3e738d180 patch
gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/1633 issue-tracking
metacpan.org/pod/Apache::Session::Generate::Random

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.