# CVE-2016-5126: Memory corruption in n/a

> Local guest users can trigger a heap buffer overflow in QEMU's iSCSI handling to crash the process or execute arbitrary code.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Jun 2016
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2016-5126, GHSA-qgv9-9qpm-r86f, UBUNTU-CVE-2016-5126

## What is CVE-2016-5126?

CVE-2016-5126 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 1 Jun 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Heap-based buffer overflow in the iscsi_aio_ioctl function in block/iscsi.c in QEMU allows local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2016-5126?

It affects 12 products.


Products: Canonical Ubuntu Linux, Debian Debian Linux, Oracle Linux, Qemu Qemu, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Tus, Redhat Enterprise Linux Workstation, Redhat Openstack, Redhat Virtualization.

## How do I fix CVE-2016-5126?

Apply the vendor's patch.

## Is CVE-2016-5126 being exploited?

There is no known exploitation of CVE-2016-5126 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-5126 and fix it if it is affected.

What it is: CVE-2016-5126 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 1 Jun 2016. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2016-5126 in the wild and no public exploit code.

Affected product: Canonical Ubuntu 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-2016-5126/ (Markdown: https://insights.sbomify.com/CVE-2016-5126/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-5126
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-5126
- OSV: https://osv.dev/vulnerability/CVE-2016-5126

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-5126/
Summaries are generated and may contain mistakes; the official description above is the record.