# CVE-2026-0396: HTML injection in the web dashboard


- **Severity:** Low 3.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 31 Mar 2026
- **Updated:** 31 Mar 2026
- **Also known as:** DEBIAN-CVE-2026-0396, GHSA-c6vq-q4cf-9cgj, UBUNTU-CVE-2026-0396

## What is CVE-2026-0396?

CVE-2026-0396 is a low-severity vulnerability in PowerDNS DNSdist, published on 31 Mar 2026. 

### Official description

An attacker might be able to inject HTML content into the internal web dashboard by sending crafted DNS queries to a DNSdist instance where domain-based dynamic rules have been enabled via either DynBlockRulesGroup:setSuffixMatchRule or DynBlockRulesGroup:setSuffixMatchRuleFFI.

Weakness: CWE-80 (Improper Neutralization of Script-Related HTML Tags in a Web Page)

## Which versions are affected by CVE-2026-0396?

It affects 1 product.


Products: Powerdns Dnsdist.

## How do I fix CVE-2026-0396?

Upgrade to a fixed version.

## Is CVE-2026-0396 being exploited?

There is no known exploitation of CVE-2026-0396 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-2026-0396 and fix it if it is affected.

What it is: CVE-2026-0396 is a low-severity vulnerability in PowerDNS DNSdist, published on 31 Mar 2026. 
Exploitation: There is no known exploitation of CVE-2026-0396 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-2026-0396/ (Markdown: https://insights.sbomify.com/CVE-2026-0396/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-0396
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-0396
- OSV: https://osv.dev/vulnerability/CVE-2026-0396

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-0396/
Summaries are generated and may contain mistakes; the official description above is the record.