HOMEVULNERABILITIESCVE-2019-19331
HIGH

CVE-2019-19331

CWE-407Published: December 16, 2019· Updated: Jun 17, 2026

7.5
CVSS v3.1

Official Description

knot-resolver before version 4.3.0 is vulnerable to denial of service through high CPU utilization. DNS replies with very many resource records might be processed very inefficiently, in extreme cases taking even several CPU seconds for each such uncached message. For example, a few thousand A records can be squashed into one DNS message (limit is 64kB).

NVD Source

Technical Analysis

CVE-2019-19331 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

Debian1 product(s)
debian linux
nic1 product(s)
knot resolver
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331
PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331
ADVISORYhttps://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.html
ADVISORYhttps://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.html

All References (6)

→
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331Exploit · Issue Tracking · Patch
→
https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html
→
https://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.htmlRelease Notes · Vendor Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19331Exploit · Issue Tracking · Patch
→
https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html
→
https://www.knot-resolver.cz/2019-12-04-knot-resolver-4.3.0.htmlRelease Notes · Vendor Advisory

Quick Facts

CVE IDCVE-2019-19331
CVSS Score7.5 / 10
SeverityHIGH
WeaknessCWE-407
CISA KEVNo
Affected2 vendor(s)
PublishedDec 16, 2019

Related CVEs (CWE-407)

CVE-2026-58226
8.7
CVE-2026-43967
8.7
CVE-2026-57480
8.7
CVE-2026-55206
8.7
CVE-2026-54892
8.7
CVE-2024-43483
7.5

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2019-19331 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.
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