How severe is CVE-2023-50387?

CVE-2023-50387 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-2023-50387 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 100% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-50387?

CVE-2023-50387 primarily affects Thekelleys Dnsmasq. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-50387?

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.

Does CVE-2023-50387 have an EU (EUVD) identifier?

Yes. CVE-2023-50387 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-55182.

When was CVE-2023-50387 published?

CVE-2023-50387 was published on 2024-02-14 and last updated on 2026-06-17.

CVE-2023-50387

CVE-2023-50387 is a high-severity vulnerability in Thekelleys Dnsmasq with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 100% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 100% (100th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-55182
Weakness: CWE-770
Affected product: Thekelleys Dnsmasq
Published: 2024-02-14
Last modified: 2026-06-17

Description

Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records.

Frequently asked questions

What is CVE-2023-50387?: Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records.
How severe is CVE-2023-50387?: CVE-2023-50387 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-2023-50387 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 100% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-50387?: CVE-2023-50387 primarily affects Thekelleys Dnsmasq. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-50387?: 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.
Does CVE-2023-50387 have an EU (EUVD) identifier?: Yes. CVE-2023-50387 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-55182.
When was CVE-2023-50387 published?: CVE-2023-50387 was published on 2024-02-14 and last updated on 2026-06-17.

References

Affected products (17)

cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022_23h2:-:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*
cpe:2.3:a:thekelleys:dnsmasq:*:*:*:*:*:*:*:*
cpe:2.3:a:nic:knot_resolver:*:*:*:*:*:*:*:*
cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*
cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*

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