How severe is CVE-2018-19591?

CVE-2018-19591 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-2018-19591 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-19591?

CVE-2018-19591 primarily affects Gnu Glibc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-19591?

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-2018-19591 published?

CVE-2018-19591 was published on 2018-12-04 and last updated on 2026-06-17.

CVE-2018-19591

CVE-2018-19591 is a high-severity vulnerability in Gnu Glibc 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: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Gnu Glibc
Published: 2018-12-04
Last modified: 2026-06-17

Description

In the GNU C Library (aka glibc or libc6) through 2.28, attempting to resolve a crafted hostname via getaddrinfo() leads to the allocation of a socket descriptor that is not closed. This is related to the if_nametoindex() function.

Frequently asked questions

What is CVE-2018-19591?: In the GNU C Library (aka glibc or libc6) through 2.28, attempting to resolve a crafted hostname via getaddrinfo() leads to the allocation of a socket descriptor that is not closed. This is related to the if_nametoindex() function.
How severe is CVE-2018-19591?: CVE-2018-19591 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-2018-19591 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-19591?: CVE-2018-19591 primarily affects Gnu Glibc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-19591?: 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-2018-19591 published?: CVE-2018-19591 was published on 2018-12-04 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*

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