CVE-2026-5080 Dancer::Session::Abstract versions through 1.3522 for Perl generates session ids insecurely
Insecure session ID generation in Dancer::Session::Abstract allows attackers to predict IDs and hijack user sessions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-5080?
CVE-2026-5080 is a medium-severity vulnerability in BIGPRESH Dancer::Session::Abstract, published on 30 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-5080?
It affects 1 product.
Products include Perldancer Dancer\.
How do I fix CVE-2026-5080?
Apply the vendor's patch.
Is CVE-2026-5080 being exploited?
There is no known exploitation of CVE-2026-5080 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-5080, GHSA-97p2-62hq-g269, UBUNTU-CVE-2026-5080.