# CVE-2026-96405: unbound: NLnet Labs Unbound up to and including version 1.26.1 limits compression-pointer traversal for each individual domain...

CVE-2026-96405 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2026-96405, released October 24, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-96405
- Priority: Routine
- CVSS: 5.3 (medium)
- EPSS: 0.0025
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 21, 2026

## Description

NLnet Labs Unbound up to and including version 1.26.1 limits compression-pointer traversal for each individual domain-name operation but has no aggregate inbound decompression-work budget. Many chained compression pointers in a message results in a lot of CPU usage following them. A malicious actor with recursive-query access and control of an ordinarily delegated authority that serves specially crafted replies can exploit the vulnerability and degrade Unbound's general performance.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python3-unbound amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | python3-unbound-debuginfo amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound Debian 13.5 (trixie) | 1.26.2-0+deb13u1 | [DEBIAN-CVE-2026-96405](https://patchblox.com/security/data/fix/linux/debian-cve-2026-96405.md) | Oct 24, 2026 |
| Linux | unbound Debian 14 | 1.26.2-1 | [DEBIAN-CVE-2026-96405](https://patchblox.com/security/data/fix/linux/debian-cve-2026-96405.md) | Oct 24, 2026 |
| Linux | unbound amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-anchor amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-anchor-debuginfo amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-debuginfo amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-debugsource amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-devel amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-libs amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-libs-debuginfo amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-utils amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |
| Linux | unbound-utils-debuginfo amzn 2023 | 1.17.1-1.amzn2023.0.17 | [ALAS2023-2026-3313](https://patchblox.com/security/data/fix/linux/alas2023-2026-3313.md) | Nov 7, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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