# CVE-2026-24030: Unbounded memory allocation for DoQ and DoH3

> Attackers can cause denial of service in PowerDNS DNSdist by triggering unbounded memory allocation during QUIC or HTTP/3 processing.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 31 Mar 2026
- **Updated:** 31 Mar 2026
- **Also known as:** DEBIAN-CVE-2026-24030, GHSA-v2vv-6q75-rvc9, UBUNTU-CVE-2026-24030

## What is CVE-2026-24030?

CVE-2026-24030 is a medium-severity denial of service vulnerability in PowerDNS DNSdist, published on 31 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An attacker might be able to trick DNSdist into allocating too much memory while processing DNS over QUIC or DNS over HTTP/3 payloads, resulting in a denial of service. In setups with a large quantity of memory available this usually results in an exception and the QUIC connection is properly closed, but in some cases the system might enter an out-of-memory state instead and terminate the process.

Weakness: CWE-789 (Memory Allocation with Excessive Size Value)

## Which versions are affected by CVE-2026-24030?

It affects 1 product.


Products: Powerdns Dnsdist.

## How do I fix CVE-2026-24030?

Upgrade to a fixed version.

## Is CVE-2026-24030 being exploited?

There is no known exploitation of CVE-2026-24030 in the wild and no public exploit code.

## Other vulnerabilities in PowerDNS DNSdist

- [CVE-2017-7557](https://insights.sbomify.com/CVE-2017-7557/): Cross-site request forgery in dnsdist (high 8.8)
- [CVE-2026-33593](https://insights.sbomify.com/CVE-2026-33593/): Denial of service via crafted DNSCrypt query (high 7.5)
- [CVE-2026-33602](https://insights.sbomify.com/CVE-2026-33602/): Off-by-one access when processing crafted UDP responses (medium 6.5)
- [CVE-2026-24029](https://insights.sbomify.com/CVE-2026-24029/): DNS over HTTPS ACL bypass (medium 6.5)
- [CVE-2026-27853](https://insights.sbomify.com/CVE-2026-27853/): Out-of-bounds write when rewriting large DNS packets (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-24030 and fix it if it is affected.

What it is: CVE-2026-24030 is a medium-severity denial of service vulnerability in PowerDNS DNSdist, published on 31 Mar 2026. 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-2026-24030 in the wild and no public exploit code.

Affected product: PowerDNS DNSdist. 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-2026-24030/ (Markdown: https://insights.sbomify.com/CVE-2026-24030/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-24030
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-24030
- OSV: https://osv.dev/vulnerability/CVE-2026-24030

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-24030/
Summaries are generated and may contain mistakes; the official description above is the record.