# CVE-2026-64193: libnet-dns-perl: Net::DNS versions through 1.55 for Perl allow remote execution injection via EDNS EXTENDED ERROR

CVE-2026-64193 is fixed in 4 products on 1 platform, first by DEBIAN-CVE-2026-64193, released July 24, 2026. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2026-64193
- Priority: Urgent
- CVSS: 9.8 (critical)
- EPSS: 0.0144
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 20, 2026

## Description

Net::DNS versions through 1.55 for Perl allow remote execution injection via EDNS EXTENDED ERROR.  Net::DNS::RR::OPT::EXTENDED_ERROR::_decompose parses the EXTRA-TEXT field of an EDNS EXTENDED-ERROR option (RFC 8914) by tokenising the raw bytes and passing the result to Perl's eval. There is some escaping done for $ and @, but not for backticks. This can be exploited for command execution if $pkt->edns->option('EXTENDED-ERROR') is called in array context, for example with a payload of {0:`"<command>"`} in EXTRA-TEXT.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libnet-dns-perl Debian 13.5 (trixie) | 1.56-0+deb13u1 | [DEBIAN-CVE-2026-64193](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64193.md) | Jul 24, 2026 |
| Linux | libnet-dns-perl Debian 14 | 1.56-1 | [DEBIAN-CVE-2026-64193](https://patchblox.com/security/data/fix/linux/debian-cve-2026-64193.md) | Jul 24, 2026 |
| Linux | perl-Net-DNS amzn 2023 | 1.56-1.amzn2023.0.1 | [ALAS2023-2026-2046](https://patchblox.com/security/data/fix/linux/alas2023-2026-2046.md) | Aug 3, 2026 |
| Linux | perl-Net-DNS opensuse-leap 16.0 | 1.570.0-bp160.1.1 | [OPENSUSE-SU-2026:21859-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21859-1.md) | Sep 15, 2026 |
| Linux | perl-Net-DNS-Nameserver amzn 2023 | 1.56-1.amzn2023.0.1 | [ALAS2023-2026-2046](https://patchblox.com/security/data/fix/linux/alas2023-2026-2046.md) | Aug 3, 2026 |
| Linux | perl-Net-DNS-tests amzn 2023 | 1.56-1.amzn2023.0.1 | [ALAS2023-2026-2046](https://patchblox.com/security/data/fix/linux/alas2023-2026-2046.md) | Aug 3, 2026 |

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Data as of 2026-11-08T19:12:23Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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