Quick answers
- Is CVE-2026-123585 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123585 being exploited in the wild.
- How severe is CVE-2026-123585?
- Medium severity, with a CVSS score of 5.3, published 8 November 2026.
- Which products and versions are affected?
- Hickory-Dns Hickory-Resolver 0.25.0 before 0.26.2.
- Is there a fix for CVE-2026-123585?
- Yes: fixed in 0.26.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123585 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-123585?
- Check whether you run 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: 0.26.2
Technical details
The hickory-resolver component follows CNAME records that appear in DNS response authority and additional sections, or that are not part of the CNAME chain from the original query name. An attacker controlling DNS responses can inject these irrelevant CNAME records to cause the resolver to send unnecessary queries, amplifying query traffic beyond what is required to resolve the original request. This is a resource consumption vulnerability (CWE-400) exploitable over the network without authentication.
Affected products
- Hickory DNS hickory-resolver 0.25.0 before 0.26.2
Timeline
- 2026-09-03: disclosed
- 2026-11-08: advisory