# GHSA-2fhr-8r8r-qp56: ZendFramework Information Disclosure and Insufficient Entropy vulnerability

> Weak random number generation in Zend Framework CAPTCHA allows attackers to bypass challenges and potentially disclose information.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Jun 2024

## What is GHSA-2fhr-8r8r-qp56?

GHSA-2fhr-8r8r-qp56 is a vulnerability in zendframework/zendframework, published on 7 Jun 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Zend Framework, `Zend_Captcha_Word` (v1) and `Zend\Captcha\Word` (v2) generate a "word" for a CAPTCHA challenge by selecting a sequence of random letters from a character set. Prior to this advisory, the selection was performed using PHP's `internal array_rand()` function. This function does not generate sufficient entropy due to its usage of `rand()` instead of more cryptographically secure methods such as `openssl_pseudo_random_bytes()`. This could potentially lead to information disclosure should an attacker be able to brute force the random number generation.

## Which versions are affected by GHSA-2fhr-8r8r-qp56?

2 open source packages ship an affected version, including zendframework/zendframework.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `zendframework/zendframework` | Packagist | From 2.0.0 | 2.4.9 |
| `zendframework/zendframework` | Packagist | From 2.0.0 | 2.4.9 |

## How do I fix GHSA-2fhr-8r8r-qp56?

Upgrade zendframework/zendframework to 2.4.9 or later.

## Is GHSA-2fhr-8r8r-qp56 being exploited?

There is no known exploitation of GHSA-2fhr-8r8r-qp56 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-2fhr-8r8r-qp56 and fix it if it is affected.

What it is: GHSA-2fhr-8r8r-qp56 is a vulnerability in zendframework/zendframework, published on 7 Jun 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-2fhr-8r8r-qp56 in the wild and no public exploit code.

Affected packages and fixed versions:
- zendframework/zendframework (Packagist): affected from 2.0.0; fixed in 2.4.9
- zendframework/zendframework (Packagist): affected from 2.0.0; fixed in 2.4.9

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/GHSA-2fhr-8r8r-qp56/ (Markdown: https://insights.sbomify.com/GHSA-2fhr-8r8r-qp56/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-2fhr-8r8r-qp56

---
From sbomify Insights: https://insights.sbomify.com/GHSA-2fhr-8r8r-qp56/
Summaries are generated and may contain mistakes; the official description above is the record.