CVE-2026-66374: nic knot_resolver
CVSS: 8.1v3.1HighDeferred
AliasesUBUNTU-CVE-2026-66374DEBIAN-CVE-2026-66374
Published 25-07-2026Last modified 27-07-2026
Vulnerability summary
CVE-2026-66374 is a high (CVSS 8.1) vulnerability in nic knot_resolver. EPSS estimates a 0.62% chance of exploitation in the next 30 days, higher than 48.9% of scored vulnerabilities.
CVSS score
8.1/10
010
High · v3.1 (CVE.org)EPSS score
0.62%
0%100%
Low · +0.13 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 25-07-2026PublishedVulnerability first disclosed.
- 27-07-2026Last modifiedVulnerability information updated.
Description
Knot Resolver before 6.4.1 allows remote code execution via a heap-based buffer overflow in the DoQ (DNS-over-QUIC) receive path.
CVSS metrics
4 scores · 4 sources · 1 versionHigh 8.1Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:LSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:L
- OSV · DebianEcosystem advisory · calculated8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:L
- NVDNIST8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:L
EPSS trend
Probability
0.62%
Chance of exploitation in the next 30 days
Percentile
49%
Versus all other CVEs
30-day change
+0.13 pp
From 0.50% on 19-09-2026
19-09-202619-10-2026
EPSS score0.62%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian1 product
- knot-resolver< 6.4.1-1
Nic1 product
- knot_resolver< 6.4.1
Ubuntu1 product
- knot-resolverAll versions (No fix recorded)
3 vendors · 3 products
