# CVE-2021-43395: Denial of service in n/a

> A local unprivileged user can cause a kernel panic and deadlock via crafted filesystem operations on tmpfs, affecting illumos-based operating systems.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** No
- **Published:** 26 Dec 2022
- **Updated:** 14 Apr 2025
- **Also known as:** GHSA-6w9w-8g4v-j4m6

## What is CVE-2021-43395?

CVE-2021-43395 is a medium-severity denial of service vulnerability in Oracle Solaris, published on 26 Dec 2022. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in illumos before f859e7171bb5db34321e45585839c6c3200ebb90, OmniOS Community Edition r151038, OpenIndiana Hipster 2021.04, and SmartOS 20210923. A local unprivileged user can cause a deadlock and kernel panic via crafted rename and rmdir calls on tmpfs filesystems. Oracle Solaris 10 and 11 is also affected.

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2021-43395?

It affects 5 products.


Products: Illumos Illumos, Joyent Smartos, Omniosce Omnios, Openindiana Openindiana, Oracle Solaris.

## How do I fix CVE-2021-43395?

No fix has been published for CVE-2021-43395 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-43395 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-43395 exists.

## Other vulnerabilities in Oracle Solaris

- [CVE-2020-27678](https://insights.sbomify.com/CVE-2020-27678/): Memory corruption in n/a (critical 9.8)
- [CVE-2016-6560](https://insights.sbomify.com/CVE-2016-6560/): Integer overflow in osnet-incorporation (high 8.6)
- [CVE-2019-9579](https://insights.sbomify.com/CVE-2019-9579/): Missing authorization in n/a (high 8.1)
- [CVE-2016-6561](https://insights.sbomify.com/CVE-2016-6561/): Null dereference in osnet-incorporation (high 7.5)
- [CVE-2014-9491](https://insights.sbomify.com/CVE-2014-9491/): Null dereference in n/a (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-43395 and fix it if it is affected.

What it is: CVE-2021-43395 is a medium-severity denial of service vulnerability in Oracle Solaris, published on 26 Dec 2022. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-43395 exists.

Affected product: Oracle Solaris. 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-2021-43395/ (Markdown: https://insights.sbomify.com/CVE-2021-43395/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-43395
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-43395
- OSV: https://osv.dev/vulnerability/CVE-2021-43395

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-43395/
Summaries are generated and may contain mistakes; the official description above is the record.