# 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.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Apr 2026
- **Updated:** 30 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-5080, GHSA-97p2-62hq-g269, UBUNTU-CVE-2026-5080

## 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.

Weakness: CWE-340 (Generation of Predictable Numbers or Identifiers), CWE-338 (Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG))

## Which versions are affected by CVE-2026-5080?

It affects 1 product.


Products: 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5080 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-5080 in the wild and no public exploit code.

Affected product: BIGPRESH Dancer::Session::Abstract. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-5080/ (Markdown: https://insights.sbomify.com/CVE-2026-5080/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5080
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5080
- OSV: https://osv.dev/vulnerability/CVE-2026-5080

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5080/
Summaries are generated and may contain mistakes; the official description above is the record.