CVE-2023-32067

0-byte UDP payload DoS in c-ares

HIGH
7.5
CVSS Score
Published: May 25, 2023 at 10:49 PM UTC
Updated: June 17, 2026 at 05:58 AM UTC
4 products affected across 4 vendorsDebian LinuxFedoraC Ares

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Severity
HIGH7.5
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

c-ares is an asynchronous resolver library. c-ares is vulnerable to denial of service. If a target resolver sends a query, the attacker forges a malformed UDP packet with a length of 0 and returns them to the target resolver. The target resolver erroneously interprets the 0 length as a graceful shutdown of the connection. This issue has been patched in version 1.19.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.19.1
Affected range stops below 1.19.1, so it looks safe — our inference, not a vendor statement
v < 1.19.1
Affected range stops below 1.19.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-400NVD-CWE-noinfo

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