# CVE-2026-5087: PAGI::Middleware::Session::Store::Cookie versions through 0.001003 for Perl generates random bytes insecurely

> Insecure random number generation for session cookie IVs allows attackers to decrypt and tamper with session data.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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:** 31 Mar 2026
- **Updated:** 1 Apr 2026
- **Also known as:** GHSA-r6mr-wmgj-f864

## What is CVE-2026-5087?

CVE-2026-5087 is a high-severity vulnerability in JJNAPIORK PAGI::Middleware::Session::Store::Cookie, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

PAGI::Middleware::Session::Store::Cookie versions through 0.001003 for Perl generates random bytes insecurely.

PAGI::Middleware::Session::Store::Cookie attempts to read bytes from the /dev/urandom device directly. If that fails (for example, on systems without the device, such as Windows), then it will emit a warning that recommends the user install Crypt::URandom, and then return a string of random bytes generated by the built-in rand function, which is unsuitable for cryptographic applications.

This modules does not use the Crypt::URandom module, and installing it will not fix the problem.

The random bytes are used for generating an initialisation vector (IV) to encrypt the cookie.

A predictable IV may make it easier for malicious users to decrypt and tamper with the session data that is stored in the cookie.

Weakness: CWE-338 (Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)), CWE-1204 (Generation of Weak Initialization Vector (IV))

## Which versions are affected by CVE-2026-5087?

It affects 1 product.


Products: Jjnapiork Pagi\.

## How do I fix CVE-2026-5087?

No fix has been published for CVE-2026-5087 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5087 being exploited?

There is no known exploitation of CVE-2026-5087 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5087 and fix it if it is affected.

What it is: CVE-2026-5087 is a high-severity vulnerability in JJNAPIORK PAGI::Middleware::Session::Store::Cookie, published on 31 Mar 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-2026-5087 in the wild and no public exploit code.

Affected product: JJNAPIORK PAGI::Middleware::Session::Store::Cookie. 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-2026-5087/ (Markdown: https://insights.sbomify.com/CVE-2026-5087/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5087
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5087
- OSV: https://osv.dev/vulnerability/CVE-2026-5087

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-5087/
Summaries are generated and may contain mistakes; the official description above is the record.