Is CVE-2026-123606 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-123606 being exploited in the wild.

How severe is CVE-2026-123606?

High severity, with a CVSS score of 7.5, published 8 November 2026.

Which products and versions are affected?

Hickory-Dns Hickory-Recursor 0.25.0-alpha.3 through 0.25.2; Hickory-Dns Hickory-Resolver 0.26.0-alpha.1 before 0.26.2.

Is there a fix for CVE-2026-123606?

Yes: fixed in hickory-resolver 0.26.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-123606 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-123606?

Check whether you run Hickory-Dns Hickory-Recursor or Hickory-Dns Hickory-Resolver at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-123606: hickory-dns recursor glueless-NS referral amplification

CVE-2026-123606 · Severity: high · CVSS 7.5 · Published 2026-11-08

The hickory-dns DNS recursor library recursively resolves domain names for applications and services. A flaw in how it handles DNS referrals without glue records allows attackers to trigger excessive lookups by crafting specially crafted referrals, potentially amplifying traffic against upstream DNS servers or exhausting the recursor's own resources and degrading service availability.

Technologies: Hickory-Dns Hickory-Recursor, Hickory-Dns Hickory-Resolver. Vendors: Hickory-Dns.

Quick answers

Is CVE-2026-123606 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-123606 being exploited in the wild.
How severe is CVE-2026-123606?: High severity, with a CVSS score of 7.5, published 8 November 2026.
Which products and versions are affected?: Hickory-Dns Hickory-Recursor 0.25.0-alpha.3 through 0.25.2; Hickory-Dns Hickory-Resolver 0.26.0-alpha.1 before 0.26.2.
Is there a fix for CVE-2026-123606?: Yes: fixed in hickory-resolver 0.26.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123606 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-123606?: Check whether you run Hickory-Dns Hickory-Recursor or Hickory-Dns Hickory-Resolver at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: hickory-resolver 0.26.2

Technical details

The hickory-dns recursor lacks a per-query work budget when processing out-of-bailiwick NS targets without glue records in referrals. An attacker can serve referrals with many glueless NS records, causing the recursor to issue separate A and AAAA lookups for each target, exploiting the absence of referral width limits. This is similar to the NXNSAttack (CVE-2020-8616/CVE-2020-12662) and can be exploited remotely without authentication.

Affected products

hickory-dns hickory-recursor 0.25.0-alpha.3 through 0.25.2
hickory-dns hickory-resolver 0.26.0-alpha.1 before 0.26.2

Timeline

2026-09-03: disclosed: GitHub Security Advisory GHSA-6h5c-jjg5-wj59 published
2026-11-08: advisory: NVD entry created

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.