How severe is CVE-2018-20743?

CVE-2018-20743 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-2018-20743 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20743?

CVE-2018-20743 primarily affects Mumble. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-20743?

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-2018-20743 published?

CVE-2018-20743 was published on 2019-01-25 and last updated on 2026-06-17.

CVE-2018-20743

CVE-2018-20743 is a high-severity vulnerability in Mumble 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mumble
Published: 2019-01-25
Last modified: 2026-06-17

Description

murmur in Mumble through 1.2.19 before 2018-08-31 mishandles multiple concurrent requests that are persisted in the database, which allows remote attackers to cause a denial of service (daemon hang or crash) via a message flood.

Frequently asked questions

What is CVE-2018-20743?: murmur in Mumble through 1.2.19 before 2018-08-31 mishandles multiple concurrent requests that are persisted in the database, which allows remote attackers to cause a denial of service (daemon hang or crash) via a message flood.
How severe is CVE-2018-20743?: CVE-2018-20743 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-2018-20743 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20743?: CVE-2018-20743 primarily affects Mumble. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-20743?: 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-2018-20743 published?: CVE-2018-20743 was published on 2019-01-25 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mumble:mumble:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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