# CVE-2019-20795: Use after free in n/a

> A use-after-free in iproute2 allows local attackers to potentially execute code or escalate privileges if setuid is enabled.

- **Severity:** Medium 4.4 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 May 2020
- **Updated:** 14 Oct 2026
- **Also known as:** ALPINE-CVE-2019-20795, DEBIAN-CVE-2019-20795, GHSA-7x5p-w7r4-hq6m, SUSE-SU-2021:3452-1, UBUNTU-CVE-2019-20795, USN-4357-1

## What is CVE-2019-20795?

CVE-2019-20795 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 9 May 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

iproute2 before 5.1.0 has a use-after-free in get_netnsid_from_name in ip/ipnetns.c. NOTE: security relevance may be limited to certain uses of setuid that, although not a default, are sometimes a configuration option offered to end users. Even when setuid is used, other factors (such as C library configuration) may block exploitability.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2019-20795?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `iproute2` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 4.12-16.6.1 |
| `iproute2` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 4.12-16.6.1 |
| `iproute2` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 4.12-16.6.1 |

Products: Canonical Ubuntu Linux, Iproute2 Project Iproute2.

## How do I fix CVE-2019-20795?

Upgrade to a fixed version.

## Is CVE-2019-20795 being exploited?

There is no known exploitation of CVE-2019-20795 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-2019-20795 and fix it if it is affected.

What it is: CVE-2019-20795 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 9 May 2020. 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-2019-20795 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-2019-20795/ (Markdown: https://insights.sbomify.com/CVE-2019-20795/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-20795
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-20795
- OSV: https://osv.dev/vulnerability/CVE-2019-20795

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-20795/
Summaries are generated and may contain mistakes; the official description above is the record.