How severe is CVE-2021-3839?

CVE-2021-3839 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-2021-3839 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3839?

CVE-2021-3839 primarily affects Redhat Enterprise Linux. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3839?

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-2021-3839 published?

CVE-2021-3839 was published on 2022-08-23 and last updated on 2026-06-17.

CVE-2021-3839

CVE-2021-3839 is a high-severity vulnerability in Redhat Enterprise Linux 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Redhat Enterprise Linux
Published: 2022-08-23
Last modified: 2026-06-17

Description

A flaw was found in the vhost library in DPDK. Function vhost_user_set_inflight_fd() does not validate `msg->payload.inflight.num_queues`, possibly causing out-of-bounds memory read/write. Any software using DPDK vhost library may crash as a result of this vulnerability.

Frequently asked questions

What is CVE-2021-3839?: A flaw was found in the vhost library in DPDK. Function vhost_user_set_inflight_fd() does not validate `msg->payload.inflight.num_queues`, possibly causing out-of-bounds memory read/write. Any software using DPDK vhost library may crash as a result of this vulnerability.
How severe is CVE-2021-3839?: CVE-2021-3839 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-2021-3839 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3839?: CVE-2021-3839 primarily affects Redhat Enterprise Linux. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3839?: 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-2021-3839 published?: CVE-2021-3839 was published on 2022-08-23 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:a:dpdk:data_plane_development_kit:*:*:*:*:*:*:*:*
cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc1:*:*:*:*:*:*
cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc2:*:*:*:*:*:*
cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc3:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
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:a:redhat:enterprise_linux_fast_datapath:7.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:enterprise_linux_fast_datapath:8.0:*:*:*:*:*:*:*

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