# CVE-2026-5084: WebDyne::Session versions before 3.003_704 for Perl generate the session id insecurely

> Insecure session ID generation in WebDyne::Session allows attackers to predict IDs and hijack user sessions.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 May 2026
- **Updated:** 2 Aug 2026
- **Also known as:** GHSA-462c-h7qr-cxm6

## What is CVE-2026-5084?

CVE-2026-5084 is a medium-severity vulnerability in ASPEER WebDyne::Session, published on 11 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

WebDyne::Session versions before 3.003_704 for Perl generate the session id insecurely.

The session handler generates the session id from an MD5 hash seeded with a call to the built-in rand() function. The rand function is passed a maximum value based on the process id, the epoch time and the reference address of the object, but this information will have no effect on the overall quality of the seed of the message digest.

The rand function is seeded by 32-bits and is predictable. It is considered unsuitable for cryptographic purposes.

Predictable session ids could allow an attacker to gain access to systems.

Note that WebDyne::Session versions 1.042 and earlier appear to be in separate distributions from WebDyne.

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-2026-5084?


## How do I fix CVE-2026-5084?

No fix has been published for CVE-2026-5084 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5084 being exploited?

There is no known exploitation of CVE-2026-5084 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5084 and fix it if it is affected.

What it is: CVE-2026-5084 is a medium-severity vulnerability in ASPEER WebDyne::Session, published on 11 May 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-2026-5084 in the wild and no public exploit code.

Affected product: ASPEER WebDyne::Session. 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-2026-5084/ (Markdown: https://insights.sbomify.com/CVE-2026-5084/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5084
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5084
- OSV: https://osv.dev/vulnerability/CVE-2026-5084

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5084/
Summaries are generated and may contain mistakes; the official description above is the record.