# CVE-2007-4840: Denial of service in n/a

> Attackers can crash PHP applications by passing long strings to specific iconv functions, causing a denial of service.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not stated
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Sep 2007
- **Updated:** 7 Aug 2024
- **Also known as:** DEBIAN-CVE-2007-4840, GHSA-pgvh-6hc4-99ch

## What is CVE-2007-4840?

CVE-2007-4840 is a medium-severity denial of service vulnerability in Php Php, published on 12 Sep 2007. It can be exploited over the network, with no action from the victim.

### Official description

PHP 5.2.4 and earlier allows context-dependent attackers to cause a denial of service (application crash) via (1) a long string in the out_charset parameter to the iconv function; or a long string in the charset parameter to the (2) iconv_mime_decode_headers, (3) iconv_mime_decode, or (4) iconv_strlen function.  NOTE: this might not be a vulnerability in most web server environments that support multiple threads, unless these issues can be demonstrated for code execution.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2007-4840?

It affects 1 product.


Products: Php Php.

## How do I fix CVE-2007-4840?

Upgrade to a fixed version.

## Is CVE-2007-4840 being exploited?

There is no known exploitation of CVE-2007-4840 in the wild and no public exploit code.

## Other vulnerabilities in Php Php

- [CVE-2012-2688](https://insights.sbomify.com/CVE-2012-2688/): Integer overflow in n/a (critical 10.0)
- [CVE-2012-2376](https://insights.sbomify.com/CVE-2012-2376/): Memory corruption in n/a (critical 10.0)
- [CVE-2011-3268](https://insights.sbomify.com/CVE-2011-3268/): Memory corruption in n/a (critical 10.0)
- [CVE-2009-4143](https://insights.sbomify.com/CVE-2009-4143/): Other in n/a (critical 10.0)
- [CVE-2008-5557](https://insights.sbomify.com/CVE-2008-5557/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2007-4840 and fix it if it is affected.

What it is: CVE-2007-4840 is a medium-severity denial of service vulnerability in Php Php, published on 12 Sep 2007. It can be exploited over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2007-4840 in the wild and no public exploit code.

Affected product: Php Php. 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-2007-4840/ (Markdown: https://insights.sbomify.com/CVE-2007-4840/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2007-4840
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2007-4840
- OSV: https://osv.dev/vulnerability/CVE-2007-4840

---
From sbomify Insights: https://insights.sbomify.com/CVE-2007-4840/
Summaries are generated and may contain mistakes; the official description above is the record.