Linux Distros Unpatched Vulnerability : CVE-2021-3593

low Nessus Plugin ID 224031

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the udp6_input() function and could occur while processing a udp packet that is smaller than the size of the 'udphdr' structure. This issue may lead to out-of-bounds read access or indirect host memory disclosure to the guest. The highest threat from this vulnerability is to data confidentiality. This flaw affects libslirp versions prior to 4.6.0. (CVE-2021-3593)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2021-3593

https://ubuntu.com/security/CVE-2021-3593

Plugin Details

Severity: Low

ID: 224031

File Name: unpatched_CVE_2021_3593.nasl

Version: 1.2

Type: local

Agent: unix

Family: Misc.

Published: 3/5/2025

Updated: 8/9/2025

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 2.4

CVSS v2

Risk Factor: Low

Base Score: 2.1

Temporal Score: 1.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N

CVSS Score Source: CVE-2021-3593

CVSS v3

Risk Factor: Low

Base Score: 3.8

Temporal Score: 3.3

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:14.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:redhat:enterprise_linux:9, cpe:/o:centos:centos:8, p-cpe:/a:redhat:enterprise_linux:qemu-kvm, p-cpe:/a:canonical:ubuntu_linux:qemu, cpe:/a:redhat:advanced_virtualization:8::el8, cpe:/o:redhat:enterprise_linux:8, p-cpe:/a:centos:centos:qemu-kvm

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 6/15/2021

Reference Information

CVE: CVE-2021-3593