CVE-2025-40916
Mojolicious::Plugin::CaptchaPNG version 1.05 for Perl uses a weak random number source for generating the captcha.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Mojolicious::Plugin::CaptchaPNG version 1.05 for Perl uses a weak random number source for generating the captcha. That version uses the built-in rand() function for generating the captcha text as well as image noise, which is insecure.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.42% probability · 36th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-338, CWE-804
- Source
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
EPSS 0.4% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://metacpan.org/pod/perlfunc#rand
- https://metacpan.org/release/GRYPHON/Mojolicious-Plugin-CaptchaPNG-1.04/diff/GRYPHON/Mojolicious-Plugin-CaptchaPNG-1.05/lib/Mojolicious/Plugin/CaptchaPNG.pm
- https://metacpan.org/release/GRYPHON/Mojolicious-Plugin-CaptchaPNG-1.06/changes
- https://security.metacpan.org/docs/guides/random-data-for-security.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.