# CVE-2018-10920: Other in knot-resolver

> Remote attackers can poison the DNS cache due to improper input validation in Knot Resolver, affecting DNS integrity.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Aug 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-10920, GHSA-xv4h-w5rx-q9c8, UBUNTU-CVE-2018-10920

## What is CVE-2018-10920?

CVE-2018-10920 is a high-severity vulnerability in cz.nic knot-resolver, published on 2 Aug 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper input validation bug in DNS resolver component of Knot Resolver before 2.4.1 allows remote attacker to poison cache.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2018-10920?

It affects 1 product.


Products: Nic Knot Resolver.

## How do I fix CVE-2018-10920?

Upgrade to a fixed version.

## Is CVE-2018-10920 being exploited?

There is no known exploitation of CVE-2018-10920 in the wild and no public exploit code.

Public exploit code:

- Knot Resolver CVE-2018-10920 / DO NOT ABUSE (github_poc): https://github.com/shutingrz/CVE-2018-10920_PoC

## Other vulnerabilities in cz.nic knot-resolver

- [CVE-2023-46317](https://insights.sbomify.com/CVE-2023-46317/): Denial of service in n/a (high 7.5)
- [CVE-2023-26249](https://insights.sbomify.com/CVE-2023-26249/): Denial of service in n/a (high 7.5)
- [CVE-2021-40083](https://insights.sbomify.com/CVE-2021-40083/): Denial of service in n/a (high 7.5)
- [CVE-2018-1110](https://insights.sbomify.com/CVE-2018-1110/): Denial of service in knot-resolver (high 7.5)
- [CVE-2020-12667](https://insights.sbomify.com/CVE-2020-12667/): Denial of service in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-10920 and fix it if it is affected.

What it is: CVE-2018-10920 is a high-severity vulnerability in cz.nic knot-resolver, published on 2 Aug 2018. 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-2018-10920 in the wild and no public exploit code.

Affected product: cz.nic knot-resolver. 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-2018-10920/ (Markdown: https://insights.sbomify.com/CVE-2018-10920/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-10920
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-10920
- OSV: https://osv.dev/vulnerability/CVE-2018-10920

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-10920/
Summaries are generated and may contain mistakes; the official description above is the record.