CVE-2025-40918Authen::SASL::Perl::DIGEST_MD5 versions 2.04 through 2.1800 for Perl generates the cnonce insecurely
- 6.5MediumCVSS base score
- 0.46%Exploitation in 30 daysEPSS · top 60% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Authen::SASL::Perl::DIGEST_MD5 versions 2.04 through 2.1800 for Perl generates the cnonce insecurely. The cnonce (client nonce) is generated from an MD5 hash of the PID, the epoch time and the built-in rand function. 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. According to RFC 2831, The cnonce-value is an opaque quoted string value provided by the client and used by both client and server to avoid chosen plaintext attacks, and to provide mutual authentication. The security of the implementation depends on a good choice. It is RECOMMENDED that it contain at least 64 bits of entropy.
Timeline
ID reserved
By CPANSec
- 3 months later
· 3 months later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.46% · top 60% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Affected products
EHUELS · Authen::SASL::Perl::DIGEST_MD5
- affected 2.04 – ≤ 2.1800
What to do
Solution: Users should upgrade to version 2.1900 or later.
References
References6
- https://metacpan.org/release/EHUELS/Authen-SASL-2.1900/changes (opens in a new tab)
- https://metacpan.org/dist/Authen-SASL/source/lib/Authen/SASL/Perl/DIGEST_MD5.pm#L263 (opens in a new tab)
- https://datatracker.ietf.org/doc/html/rfc2831 (opens in a new tab)
- https://security.metacpan.org/patches/A/Authen-SASL/2.1800/CVE-2025-40918-r1.patch (opens in a new tab)patch
- https://github.com/gbarr/perl-authen-sasl/pull/22 (opens in a new tab)issue-tracking
- http://www.openwall.com/lists/oss-security/2025/07/16/5 (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)
- EUVD EUVD-2025-21696 (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://cveledger.app/cve/CVE-2025-40918)Record last updated .