How severe is CVE-2018-20191?

CVE-2018-20191 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-2018-20191 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20191?

CVE-2018-20191 primarily affects Qemu. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-20191?

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-2018-20191 published?

CVE-2018-20191 was published on 2018-12-20 and last updated on 2026-06-17.

CVE-2018-20191

CVE-2018-20191 is a high-severity vulnerability in Qemu 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Qemu
Published: 2018-12-20
Last modified: 2026-06-17

Description

hw/rdma/vmw/pvrdma_main.c in QEMU does not implement a read operation (such as uar_read by analogy to uar_write), which allows attackers to cause a denial of service (NULL pointer dereference).

Frequently asked questions

What is CVE-2018-20191?: hw/rdma/vmw/pvrdma_main.c in QEMU does not implement a read operation (such as uar_read by analogy to uar_write), which allows attackers to cause a denial of service (NULL pointer dereference).
How severe is CVE-2018-20191?: CVE-2018-20191 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-2018-20191 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20191?: CVE-2018-20191 primarily affects Qemu. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-20191?: 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-2018-20191 published?: CVE-2018-20191 was published on 2018-12-20 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*

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