# CVE-2026-42387: pdns-recursor: A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Re...

CVE-2026-42387 is fixed in pdns-recursor on 1 platform, first by DEBIAN-CVE-2026-42387, released June 26, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-42387
- Priority: Routine
- CVSS: 5.9 (medium)
- EPSS: 0.0048
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 25, 2026

## Description

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | pdns-recursor Debian 13.5 (trixie) | 5.2.11-0+deb13u1 | [DEBIAN-CVE-2026-42387](https://patchblox.com/security/data/fix/linux/debian-cve-2026-42387.md) | Jun 26, 2026 |
| Linux | pdns-recursor Debian 14 | 5.4.3-1 | [DEBIAN-CVE-2026-42387](https://patchblox.com/security/data/fix/linux/debian-cve-2026-42387.md) | Jun 26, 2026 |

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Data as of 2026-11-08T06:59:42Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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