Debian DLA-2753-1 : qemu - LTS security update

high Nessus Plugin ID 152982

Synopsis

The remote Debian host is missing one or more security-related updates.

Description

The remote Debian 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-2753 advisory.

- A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB packets are combined into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk transfer is used to dynamically allocate a variable length array (VLA) on the stack without proper validation. Since the total size is not bounded, a malicious guest could use this flaw to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service. (CVE-2021-3527)

- An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the bootp_input() function and could occur while processing a udp packet that is smaller than the size of the 'bootp_t' structure. A malicious guest could use this flaw to leak 10 bytes of uninitialized heap memory from the host. The highest threat from this vulnerability is to data confidentiality. This flaw affects libslirp versions prior to 4.6.0. (CVE-2021-3592)

- An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the udp_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-2021-3594)

- An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the tftp_input() function and could occur while processing a udp packet that is smaller than the size of the 'tftp_t' 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-2021-3595)

- A flaw was found in the USB redirector device emulation of QEMU in versions prior to 6.1.0-rc2. It occurs when dropping packets during a bulk transfer from a SPICE client due to the packet queue being full. A malicious SPICE client could use this flaw to make QEMU call free() with faked heap chunk metadata, resulting in a crash of QEMU or potential code execution with the privileges of the QEMU process on the host. (CVE-2021-3682)

- An out-of-bounds write flaw was found in the UAS (USB Attached SCSI) device emulation of QEMU in versions prior to 6.2.0-rc0. The device uses the guest supplied stream number unchecked, which can lead to out-of- bounds access to the UASDevice->data3 and UASDevice->status3 fields. A malicious guest user could use this flaw to crash QEMU or potentially achieve code execution with the privileges of the QEMU process on the host. (CVE-2021-3713)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade the qemu packages.

For Debian 9 stretch, these problems have been fixed in version 1

See Also

https://security-tracker.debian.org/tracker/source-package/qemu

https://packages.debian.org/source/stretch/qemu

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=988157

https://www.debian.org/lts/security/2021/dla-2753

https://security-tracker.debian.org/tracker/CVE-2021-3527

https://security-tracker.debian.org/tracker/CVE-2021-3592

https://security-tracker.debian.org/tracker/CVE-2021-3594

https://security-tracker.debian.org/tracker/CVE-2021-3595

https://security-tracker.debian.org/tracker/CVE-2021-3682

https://security-tracker.debian.org/tracker/CVE-2021-3713

Plugin Details

Severity: High

ID: 152982

File Name: debian_DLA-2753.nasl

Version: 1.2

Type: local

Agent: unix

Published: 9/3/2021

Updated: 9/3/2021

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.5

CVSS v2

Risk Factor: Medium

Base Score: 6

Temporal Score: 4.4

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

CVSS Score Source: CVE-2021-3682

CVSS v3

Risk Factor: High

Base Score: 8.5

Temporal Score: 7.4

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

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

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:qemu, p-cpe:/a:debian:debian_linux:qemu-block-extra, p-cpe:/a:debian:debian_linux:qemu-guest-agent, p-cpe:/a:debian:debian_linux:qemu-kvm, p-cpe:/a:debian:debian_linux:qemu-system, p-cpe:/a:debian:debian_linux:qemu-system-arm, p-cpe:/a:debian:debian_linux:qemu-system-common, p-cpe:/a:debian:debian_linux:qemu-system-mips, p-cpe:/a:debian:debian_linux:qemu-system-misc, p-cpe:/a:debian:debian_linux:qemu-system-ppc, p-cpe:/a:debian:debian_linux:qemu-system-sparc, p-cpe:/a:debian:debian_linux:qemu-system-x86, p-cpe:/a:debian:debian_linux:qemu-user, p-cpe:/a:debian:debian_linux:qemu-user-binfmt, p-cpe:/a:debian:debian_linux:qemu-user-static, p-cpe:/a:debian:debian_linux:qemu-utils, cpe:/o:debian:debian_linux:9.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 9/2/2021

Vulnerability Publication Date: 5/26/2021

Reference Information

CVE: CVE-2021-3527, CVE-2021-3592, CVE-2021-3594, CVE-2021-3595, CVE-2021-3682, CVE-2021-3713