CVE-2026-0398 | Crafted zones can lead to increased resource usage and crafted CNAME chains can lead to cache poisoning in Recursor

Crafted zones can lead to increased resource usage and crafted CNAME chains can lead to cache poisoning in Recursor.

Published: 2026-02-09 Last update: 2026-04-20 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-0398 is rated Low Risk (21.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). 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-2026-0398

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 2026-02-10 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-0398

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L 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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2026-0398

OS Trackers for CVE-2026-0398

vendor priority summary link
alpine — CVE-2026-0398: 1 source package rows (pdns-recursor); 2 state rows across 2 repos (3.23-community, edge-community); fixed 2, open 0. https://security.alpinelinux.org/vuln/CVE-2026-0398
debian end-of-life CVE-2026-0398 end-of-life priority: Debian including 1 source packages (pdns-recursor), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2026-0398
ubuntu medium CVE-2026-0398 medium priority: Ubuntu including 1 source packages (pdns-recursor), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): needs-triage 7. https://ubuntu.com/security/CVE-2026-0398

Affected software / configurations for CVE-2026-0398

Vendor Product Version Raw CPE
powerdns recursor >= 5.1.0, < 5.1.10 cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*
powerdns recursor >= 5.2.8, < 5.2.8 cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*
powerdns recursor >= 5.3.0, < 5.3.5 cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*

References for CVE-2026-0398

cvelogic Threat Intelligence