# CVE-2015-5291: Memory corruption in n/a

> Remote attackers can cause client crashes or execute arbitrary code via a long hostname in the SNI extension of an SSL handshake.

- **Severity:** Medium 6.8 (`AV:N/AC:M/Au:N/C:P/I:P/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Nov 2015
- **Updated:** 6 Aug 2024
- **Also known as:** DLA-331-1, GHSA-hhcq-g9mx-qpfg

## What is CVE-2015-5291?

CVE-2015-5291 is a medium-severity memory corruption vulnerability in Debian Debian Linux, published on 2 Nov 2015. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Heap-based buffer overflow in PolarSSL 1.x before 1.2.17 and ARM mbed TLS (formerly PolarSSL) 1.3.x before 1.3.14 and 2.x before 2.1.2 allows remote SSL servers to cause a denial of service (client crash) and possibly execute arbitrary code via a long hostname to the server name indication (SNI) extension, which is not properly handled when creating a ClientHello message.  NOTE: this identifier has been SPLIT per ADT3 due to different affected version ranges. See CVE-2015-8036 for the session ticket issue that was introduced in 1.3.0.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2015-5291?

It affects 6 products.


Products: Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Opensuse Opensuse, Polarssl Polarssl, Trustedfirmware Mbed Tls.

## How do I fix CVE-2015-5291?

Upgrade to a fixed version.

## Is CVE-2015-5291 being exploited?

There is no known exploitation of CVE-2015-5291 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-5291 and fix it if it is affected.

What it is: CVE-2015-5291 is a medium-severity memory corruption vulnerability in Debian Debian Linux, published on 2 Nov 2015. 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-2015-5291 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2015-5291/ (Markdown: https://insights.sbomify.com/CVE-2015-5291/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-5291
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-5291
- OSV: https://osv.dev/vulnerability/CVE-2015-5291

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-5291/
Summaries are generated and may contain mistakes; the official description above is the record.