How severe is CVE-2019-9917?

CVE-2019-9917 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-9917 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-9917?

CVE-2019-9917 primarily affects Znc. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-9917?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-9917 published?

CVE-2019-9917 was published on 2019-03-27 and last updated on 2026-06-17.

CVE-2019-9917

CVE-2019-9917 is a medium-severity vulnerability in Znc with a CVSS 3.x base score of 6.5. 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: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Znc
Published: 2019-03-27
Last modified: 2026-06-17

Description

ZNC before 1.7.3-rc1 allows an existing remote user to cause a Denial of Service (crash) via invalid encoding.

Frequently asked questions

What is CVE-2019-9917?: ZNC before 1.7.3-rc1 allows an existing remote user to cause a Denial of Service (crash) via invalid encoding.
How severe is CVE-2019-9917?: CVE-2019-9917 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-9917 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-9917?: CVE-2019-9917 primarily affects Znc. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-9917?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-9917 published?: CVE-2019-9917 was published on 2019-03-27 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:znc:znc:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*

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