# CVE-2010-4156: Information disclosure in n/a

> Attackers can obtain sensitive information via a large length parameter in the mb_strcut function of the Libmbfl library used by PHP.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:P/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:** Yes
- **Published:** 10 Nov 2010
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-9mqx-xjgw-xp5v

## What is CVE-2010-4156?

CVE-2010-4156 is a medium-severity vulnerability in n/a, published on 10 Nov 2010. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The mb_strcut function in Libmbfl 1.1.0, as used in PHP 5.3.x through 5.3.3, allows context-dependent attackers to obtain potentially sensitive information via a large value of the third parameter (aka the length parameter).

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2010-4156?

It affects 1 product.


Products: Scottmac Libmbfl.

## How do I fix CVE-2010-4156?

Upgrade to a fixed version.

## Is CVE-2010-4156 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2010-4156 exists.

Public exploit code:

- PHP 5.3.x - 'mb_strcut()' Information Disclosure (exploitdb)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2010-4156 and fix it if it is affected.

What it is: CVE-2010-4156 is a medium-severity vulnerability in n/a, published on 10 Nov 2010. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2010-4156 exists.

Affected product: n/a. 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-2010-4156/ (Markdown: https://insights.sbomify.com/CVE-2010-4156/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2010-4156
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2010-4156
- OSV: https://osv.dev/vulnerability/CVE-2010-4156

---
From sbomify Insights: https://insights.sbomify.com/CVE-2010-4156/
Summaries are generated and may contain mistakes; the official description above is the record.