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.

Published: 2022-08-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3839 is rated Moderate Risk (53.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.21%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3839

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.59% 1.21% +0.62%
2 2026-04-19 0.47% 0.59% +0.12%
3 2026-02-16 — 0.47% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3839

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2021-3839

OS Trackers for CVE-2021-3839

vendor priority summary link
debian not yet assigned CVE-2021-3839 not yet assigned priority: Debian including 1 source packages (dpdk), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-3839
redhat medium — https://access.redhat.com/security/cve/CVE-2021-3839
suse medium CVE-2021-3839 severity moderate: SUSE including 67 source package names (dpdk, dpdk-19.11.10-150400.2.10, …), 223 product×package rows across 50 product lines (HPE Helion OpenStack 8, SUSE CaaS Platform 4.0, … (50 product lines)): Fixed 125, Known Not Affected 98. https://www.suse.com/security/cve/CVE-2021-3839/
ubuntu medium CVE-2021-3839 medium priority: Ubuntu including 1 source packages (dpdk), 7 status rows across 7 suites (bionic, focal, impish, jammy, kinetic, upstream, xenial): released 4, not-affected 2, needs-triage 1. https://ubuntu.com/security/CVE-2021-3839

Affected software / configurations for CVE-2021-3839

Vendor Product Version Raw CPE
dpdk data_plane_development_kit < 22.03 cpe:2.3:a:dpdk:data_plane_development_kit:*:*:*:*:*:*:*:*
dpdk data_plane_development_kit 22.03 cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc1:*:*:*:*:*:*
dpdk data_plane_development_kit 22.03 cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc2:*:*:*:*:*:*
dpdk data_plane_development_kit 22.03 cpe:2.3:a:dpdk:data_plane_development_kit:22.03:rc3:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
redhat enterprise_linux_fast_datapath 7.0 cpe:2.3:a:redhat:enterprise_linux_fast_datapath:7.0:*:*:*:*:*:*:*
redhat enterprise_linux_fast_datapath 8.0 cpe:2.3:a:redhat:enterprise_linux_fast_datapath:8.0:*:*:*:*:*:*:*

References for CVE-2021-3839

cvelogic Threat Intelligence