Vulnerability in Bigpresh Dancer::session::abstract

CVE-2026-5080

Dancer::Session::Abstract versions through 1.3522 for Perl generates session ids insecurely. The session id is generated from summing the character codepoints of the absolute pathname with the process id, the epoch time and calls to the built-in rand() function to return a number between 0 and 999-billion, and concatenating that result three times. The path name might be known or guessed by an attacker, especially for applications known to be written using Dancer with standard installation locations. The epoch time can be guessed by an attacker, and may be leaked in the HTTP header. The process id comes from a small set of numbers, and workers may have sequential process ids. The built-in rand() function is seeded with 32-bits and is considered unsuitable for security applications. Predictable session ids could allow an attacker to gain access to systems.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (43.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-5080: held from 0.004 to 0.005.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5080?
CVE-2026-5080 is a medium-severity vulnerability in Bigpresh Dancer::session::abstract, classified under Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). CVSS score: 5.9/10. Published 2026-04-30.
How severe is CVE-2026-5080?
Medium severity. CVSS v3 base score is 5.9 out of 10.