CVE-2026-42254

Hickory DNS hickory-recursor 0.1 through 0.25.2 allows cross-zone poisoning because cached data is not directly associated with a query that triggered a response.

Published: 2026-04-26 Last update: 2026-04-27 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-42254 is rated Low Risk (18.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-42254

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-26 — 0.03% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-42254

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.0 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 1.4 [email protected]

Weakness enumeration for CVE-2026-42254

GitHub Security Advisory for CVE-2026-42254

GHSA-2hfw-w5cw-p4g7 · Severity: medium — Hickory DNS hickory-recursor 0.1 through 0.25.2 allows cross-zone poisoning because cached data...

OS Trackers for CVE-2026-42254

vendor priority summary link
debian not yet assigned CVE-2026-42254 not yet assigned priority: Debian including 1 source packages (rust-hickory-recursor), 3 status rows across 3 suites (forky, sid, trixie): open 3. https://security-tracker.debian.org/tracker/CVE-2026-42254
ubuntu medium CVE-2026-42254 medium priority: Ubuntu including 1 source packages (rust-hickory-recursor), 5 status rows across 5 suites (jammy, noble, questing, resolute, upstream): needs-triage 3, DNE 2. https://ubuntu.com/security/CVE-2026-42254

Affected software / configurations for CVE-2026-42254

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-42254

cvelogic Threat Intelligence