CVE-2025-40931
Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id
- Published
- Updated
- Reserved
- Assigned by
- CPANSec
Description
Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id. Apache::Session::Generate::MD5 generates session ids insecurely. The default session id generator returns a MD5 hash seeded with the built-in rand() function, the epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. Predicable session ids could allow an attacker to gain access to systems. Note that the libapache-session-perl package in some Debian-based Linux distributions may be patched to use Crypt::URandom.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| NVDNVD · Modified | 3.1 | Critical9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.64% · top 49% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.1.
Weakness
Affected products
CHORNY · Apache::Session::Generate::MD5
- affected ≤ 1.94
What to do
Solution: Consider alternate solutions like https://metacpan.org/pod/Apache::Session::Generate::Random
Workaround: Apply the patch from the Debian Perl Group that uses Crypt::URandom.
References (10)
- https://metacpan.org/dist/Apache-Session/source/lib/Apache/Session/Generate/MD5.pm#L27 (opens in a new tab)
- https://security.metacpan.org/docs/guides/random-data-for-security.html (opens in a new tab)technical-description
- https://github.com/chorny/Apache-Session/issues/4 (opens in a new tab)issue-tracking
- https://rt.cpan.org/Ticket/Display.html?id=173631 (opens in a new tab)issue-tracking
- https://www.openwall.com/lists/oss-security/2019/06/15/1 (opens in a new tab)mailing-list
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=930659 (opens in a new tab)issue-tracking
- https://salsa.debian.org/perl-team/modules/packages/libapache-session-perl/-/commit/bdabd71c2f91b18526e31a9dc52b4c17b3d246b7#898a4b8b00022df1b8689910b67707f3e738d180 (opens in a new tab)patch
- https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/1633 (opens in a new tab)issue-tracking
- https://metacpan.org/pod/Apache::Session::Generate::Random (opens in a new tab)
- http://www.openwall.com/lists/oss-security/2026/03/05/3 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2025-40931)Record last updated .