CyberSecBulletin
CVE-2026-123605NVD status: Deferred

hickory-dns: Improper Verification of Cryptographic Signature

CVE-2026-123605 is a high-severity improper verification of cryptographic signature vulnerability in hickory-dns, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, 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 0.24% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update hickory-dns to 0.26.2 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Hickory-dnshickory-dns0.1 through 0.25.0-alpha.3; 0.26.0-beta.1 up to, but not including, 0.26.20.26.2

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
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (vulncheck.com)
CVSS 3.18.8HighCNA (vulncheck.com)

Official description

Hickory DNS hickory-proto 0.1 through 0.25.0-alpha.3 and hickory-net before 0.26.2 contain a DNSSEC validation bypass because the validator verifies an RRSIG against the DNSKEY of whatever name appears in its Signer's Name field without checking that this name is the zone containing the RRset. Attackers controlling any secure zone can produce valid signatures over arbitrary records in unrelated zones, which resolvers, recursors, and clients using DnssecDnsHandle accept as authenticated.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Verification of Cryptographic Signature

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in hickory-dns

All hickory-dns vulnerabilities

Recent Improper Verification of Cryptographic Signature vulnerabilities

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