How severe is CVE-2023-32067?

CVE-2023-32067 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-32067 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-32067?

CVE-2023-32067 primarily affects C-ares Project C-ares. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-32067?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-32067 published?

CVE-2023-32067 was published on 2023-05-25 and last updated on 2026-06-17.

CVE-2023-32067

CVE-2023-32067 is a high-severity vulnerability in C-ares Project C-ares with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: C-ares Project C-ares
Published: 2023-05-25
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-32067?: 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.
How severe is CVE-2023-32067?: CVE-2023-32067 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-32067 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-32067?: CVE-2023-32067 primarily affects C-ares Project C-ares. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-32067?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-32067 published?: CVE-2023-32067 was published on 2023-05-25 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:c-ares_project:c-ares:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

More vulnerabilities in C-ares Project C-ares

CVE-2016-5180 — Critical (CVSS 9.8): Heap-based buffer overflow in the ares_create_query function in c-ares 1.x before 1.12.0 allows remote attackers to…
CVE-2022-4904 — High (CVSS 8.6): A flaw was found in the c-ares package. The ares_set_sortlist is missing checks about the validity of the input string,…
CVE-2020-8277 — High (CVSS 7.5): A Node.js application that allows an attacker to trigger a DNS request for a host of their choice could trigger a…
CVE-2017-1000381 — High (CVSS 7.5): The c-ares function `ares_parse_naptr_reply()`, which is used for parsing NAPTR responses, could be triggered to read…
CVE-2023-31147 — Medium (CVSS 5.9): c-ares is an asynchronous resolver library. When /dev/urandom or RtlGenRandom() are unavailable, c-ares uses rand() to…
CVE-2021-3672 — Medium (CVSS 5.6): A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name…

All CVEs affecting C-ares Project C-ares →

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