# CVE-2020-10030: Memory corruption in n/a

> An attacker with hostname modification privileges can trigger a stack-based out-of-bounds read in PowerDNS Recursor, leading to memory disclosure or potential code execution.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 May 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-10030, GHSA-v7fw-2gqv-66rx, UBUNTU-CVE-2020-10030

## What is CVE-2020-10030?

CVE-2020-10030 is a high-severity memory corruption vulnerability in Powerdns Recursor, published on 19 May 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough privileges to change the system's hostname) to cause disclosure of uninitialized memory content via a stack-based out-of-bounds read. It only occurs on systems where gethostname() does not have '\0' termination of the returned string if the hostname is larger than the supplied buffer. (Linux systems are not affected because the buffer is always large enough. OpenBSD systems are not affected because the returned hostname always has '\0' termination.) Under some conditions, this issue can lead to the writing of one '\0' byte out-of-bounds on the stack, causing a denial of service or possibly arbitrary code execution.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2020-10030?

It affects 1 product.


Products: Powerdns Recursor.

## How do I fix CVE-2020-10030?

Upgrade to a fixed version.

## Is CVE-2020-10030 being exploited?

There is no known exploitation of CVE-2020-10030 in the wild and no public exploit code.

## Other vulnerabilities in Powerdns Recursor

- [CVE-2009-4009](https://insights.sbomify.com/CVE-2009-4009/): Memory corruption in n/a (critical 10.0)
- [CVE-2025-59023](https://insights.sbomify.com/CVE-2025-59023/): Crafted delegations or IP fragments can poison cached delegations in Recursor (high 8.2)
- [CVE-2025-59030](https://insights.sbomify.com/CVE-2025-59030/): Insufficient validation of incoming notifies over TCP can lead to a denial of service in Recursor (high 7.5)
- [CVE-2023-22617](https://insights.sbomify.com/CVE-2023-22617/): Denial of service in n/a (high 7.5)
- [CVE-2018-16855](https://insights.sbomify.com/CVE-2018-16855/): Memory corruption in pdns-recursor (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-10030 and fix it if it is affected.

What it is: CVE-2020-10030 is a high-severity memory corruption vulnerability in Powerdns Recursor, published on 19 May 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-10030 in the wild and no public exploit code.

Affected product: Powerdns Recursor. 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-2020-10030/ (Markdown: https://insights.sbomify.com/CVE-2020-10030/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-10030
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-10030
- OSV: https://osv.dev/vulnerability/CVE-2020-10030

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-10030/
Summaries are generated and may contain mistakes; the official description above is the record.