hickory-dns: Authentication Bypass by Spoofing
CVE-2026-123580 is a high-severity authentication bypass by spoofing vulnerability in hickory-dns, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 0.26.2 as the first without the flaw, so updating hickory-dns to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.26% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update hickory-dns to 0.26.2 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Hickory-dns | hickory-dns | 0.26.0-beta.1 up to, but not including, 0.26.2; 0.26.0-alpha.1 and earlier | 0.26.2 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.5 | High | CNA (vulncheck.com) |
Official description
Hickory DNS hickory-net 0.26.0-beta.1 before 0.26.2 and hickory-proto through 0.26.0-alpha.1 perform insufficient checks on NSEC3 record names during DNSSEC verification, comparing only the hashed label without confirming the record belongs to the correct zone. Attackers can supply NSEC3 records from another zone with a matching hash label to forge DNSSEC nonexistence proofs.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authentication Bypass by Spoofing
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
More Authentication Bypass by Spoofing vulnerabilities (CWE-290)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in hickory-dns
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.8 High severity
- 7.5 High severity
- 8.8 High severity
Recent Authentication Bypass by Spoofing vulnerabilities
- 9.8 Critical severity
- 8.3 High severity
- 9.4 Critical severity
- 8.5 High severity
- 7.5 High severity
- 8.5 High severity
Spotted an error? Tell us.