# CVE-2016-9936: Use after free in n/a

> Remote attackers can cause denial of service or potentially execute code via crafted serialized data in PHP's unserialize function.

- **Severity:** Critical 9.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Jan 2017
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-jp9f-r2q5-mv5q, UBUNTU-CVE-2016-9936

## What is CVE-2016-9936?

CVE-2016-9936 is a critical use after free vulnerability in Php Php, published on 4 Jan 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The unserialize implementation in ext/standard/var.c in PHP 7.x before 7.0.14 allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via crafted serialized data.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-6834.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2016-9936?

It affects 1 product.


Products: Php Php.

## How do I fix CVE-2016-9936?

Upgrade to a fixed version.

## Is CVE-2016-9936 being exploited?

There is no known exploitation of CVE-2016-9936 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-2016-9936 and fix it if it is affected.

What it is: CVE-2016-9936 is a critical use after free vulnerability in Php Php, published on 4 Jan 2017. 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-2016-9936 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-2016-9936/ (Markdown: https://insights.sbomify.com/CVE-2016-9936/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-9936
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-9936
- OSV: https://osv.dev/vulnerability/CVE-2016-9936

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-9936/
Summaries are generated and may contain mistakes; the official description above is the record.