# CVE-2026-19630: Amplified resource exhaustion in inbound message processing


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 21 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** ALPINE-CVE-2026-19630, AZL-111506, BELL-CVE-2026-19630, DEBIAN-CVE-2026-19630, ECHO-105d-eb6f-2f1a, GHSA-53h2-668w-c49r, MINI-jp6p-g7gm-9qxx, UBUNTU-CVE-2026-19630

## What is CVE-2026-19630?

CVE-2026-19630 is a high-severity vulnerability in ISC BIND 9, published on 21 Oct 2026. 

### Official description

In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with no limit imposed by BIND.  A DNS message with a maliciously large number of such structures will cause BIND to consume disproportionate amounts of CPU time and memory during processing.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

Weakness: CWE-407 (Inefficient Algorithmic Complexity)

## Which versions are affected by CVE-2026-19630?


## How do I fix CVE-2026-19630?

Upgrade to a fixed version.

## Is CVE-2026-19630 being exploited?

There is no known exploitation of CVE-2026-19630 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19630 and fix it if it is affected.

What it is: CVE-2026-19630 is a high-severity vulnerability in ISC BIND 9, published on 21 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-19630 in the wild and no public exploit code.

Affected product: ISC BIND 9. 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-2026-19630/ (Markdown: https://insights.sbomify.com/CVE-2026-19630/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19630
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19630
- OSV: https://osv.dev/vulnerability/CVE-2026-19630

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19630/
Summaries are generated and may contain mistakes; the official description above is the record.