CVE-2025-25188 | DNSSEC validation may accept broken authentication chains

Hickory DNS is a Rust based DNS client, server, and resolver. A vulnerability present starting in version 0.8.0 and prior to versions 0.24.3 and 0.25.0-alpha.5 impacts Hickory DNS users relying on DNSSEC verification in the client library, stub resolver, or recursive resolver. The DNSSEC validation routines treat entire RRsets of DNSKEY records as trusted once they have established trust in only one of the DNSKEYs. As a result, if a zone includes a DNSKEY with a public key that matches a configured trust anchor, all keys in that zone will be trusted to authenticate other records in the zone. There is a second variant of this vulnerability involving DS records, where an authenticated DS record covering one DNSKEY leads to trust in signatures made by an unrelated DNSKEY in the same zone. Versions 0.24.3 and 0.25.0-alpha.5 fix the issue.

Published: 2025-02-10 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-25188 is rated Low Risk (30.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.07%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2025-25188

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 2026-03-21 0.02% 0.07% +0.05%
2 2025-11-21 0.08% 0.02% -0.06%
3 2025-11-18 0.08%

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-25188

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.7 4.0 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:L)
Low privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:P)
Proof-of-concept: public PoC exists; no reported exploitation and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
[email protected]

Weakness enumeration for CVE-2025-25188

GitHub Security Advisory for CVE-2025-25188

GHSA-37wc-h8xc-5hc4 · Severity: medium · Ecosystem: rust — Hickory DNS's DNSSEC validation may accept broken authentication chains

OS Trackers for CVE-2025-25188

vendor priority summary link
debian not yet assigned CVE-2025-25188 not yet assigned priority: Debian including 1 source packages (rust-hickory-proto), 3 status rows across 3 suites (forky, sid, trixie): resolved 3. https://security-tracker.debian.org/tracker/CVE-2025-25188
ubuntu medium CVE-2025-25188 medium priority: Ubuntu including 1 source packages (rust-hickory-proto), 7 status rows across 7 suites (focal, jammy, noble, oracular, plucky, questing, upstream): needs-triage 3, DNE 2, ignored 2. https://ubuntu.com/security/CVE-2025-25188

Affected software / configurations for CVE-2025-25188

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-25188

cvelogic Threat Intelligence