# CVE-2023-4236: bind9: A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an ass...

CVE-2023-4236 is fixed in 7 products on 1 platform, first by bind9 1:9.18.12-0ubuntu0.22.04.3, released September 19, 2023. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2023-4236
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0219
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 19, 2023

## Description

A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load. This issue affects BIND 9 versions 9.18.0 through 9.18.18 and 9.18.11-S1 through 9.18.18-S1.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bind9 Debian 12.15 (bookworm) | 1:9.18.19-1~deb12u1 | [DEBIAN-CVE-2023-4236](https://patchblox.com/security/data/fix/linux/debian-cve-2023-4236.md) | Sep 20, 2023 |
| Linux | bind9 Debian 13.5 (trixie) | 1:9.19.17-1 | [DEBIAN-CVE-2023-4236](https://patchblox.com/security/data/fix/linux/debian-cve-2023-4236.md) | Sep 20, 2023 |
| Linux | bind9 Debian 14 | 1:9.19.17-1 | [DEBIAN-CVE-2023-4236](https://patchblox.com/security/data/fix/linux/debian-cve-2023-4236.md) | Sep 20, 2023 |
| Linux | bind9 Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9 Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9 Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9 Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-dnsutils Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9-dnsutils 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9-dnsutils-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9-dnsutils Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9-dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9-dnsutils Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9-dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-dnsutils Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9-dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-host Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9-host 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9-host-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9-host Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9-host 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9-host-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9-host Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9-host 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9-host-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-host Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9-host 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9-host-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-libs Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9-libs 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9-libs-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9-libs Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9-libs 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9-libs-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9-libs Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9-libs 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9-libs-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-libs Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9-libs 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9-libs-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-utils Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9-utils 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9-utils-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9-utils Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9-utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9-utils-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9-utils Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9-utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9-utils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9-utils Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9-utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9-utils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9utils Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [bind9utils 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-bind9utils-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | bind9utils Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [bind9utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-bind9utils-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | bind9utils Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [bind9utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-bind9utils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | bind9utils Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [bind9utils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-bind9utils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | dnsutils Ubuntu 22.04.1 LTS (jammy) | 1:9.18.12-0ubuntu0.22.04.3 | [dnsutils 1:9.18.12-0ubuntu0.22.04.3](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-dnsutils-1-9.18.12-0ubuntu0.22.04.3.md) | Sep 19, 2023 |
| Linux | dnsutils Ubuntu 24.04.5 LTS (noble) | 1:9.18.18-0ubuntu2 | [dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-noble-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 19, 2023 |
| Linux | dnsutils Ubuntu 24.10 (oracular) | 1:9.18.18-0ubuntu2 | [dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |
| Linux | dnsutils Ubuntu 25.04 (plucky) | 1:9.18.18-0ubuntu2 | [dnsutils 1:9.18.18-0ubuntu2](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-dnsutils-1-9.18.18-0ubuntu2.md) | Sep 20, 2023 |

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