What is CVE-2026-64193?

CVE-2026-64193 is a critical-severity vulnerability in Nlnetlabs Net::dns, classified under Eval Injection. CVSS score: 9.8/10. Published 2026-07-20.

How severe is CVE-2026-64193?

Critical severity. CVSS v3 base score is 9.8 out of 10.

RCE in Nlnetlabs Net::dns

CVE-2026-64193

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.

EPSS: 0.008 (53.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Nlnetlabs Net::dns — versions 0

Weakness classification (CWE)

CWE-95 — Eval Injection

References

9b29abf9-4ab0-4765-b253-1875cd9b441e
9b29abf9-4ab0-4765-b253-1875cd9b441e (issue-tracking)
9b29abf9-4ab0-4765-b253-1875cd9b441e (release-notes)
af854a3a-2127-422b-91ae-364da2661108

Frequently asked questions

What is CVE-2026-64193?: CVE-2026-64193 is a critical-severity vulnerability in Nlnetlabs Net::dns, classified under Eval Injection. CVSS score: 9.8/10. Published 2026-07-20.
How severe is CVE-2026-64193?: Critical severity. CVSS v3 base score is 9.8 out of 10.