Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 23.10 : X.Org X Server vulnerabilities (USN-6721-1)

high Nessus Plugin ID 192938

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 23.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6721-1 advisory.

- A heap-based buffer over-read vulnerability was found in the X.org server's ProcXIGetSelectedEvents() function. This issue occurs when byte-swapped length values are used in replies, potentially leading to memory leakage and segmentation faults, particularly when triggered by a client with a different endianness. This vulnerability could be exploited by an attacker to cause the X server to read heap memory values and then transmit them back to the client until encountering an unmapped page, resulting in a crash. Despite the attacker's inability to control the specific memory copied into the replies, the small length values typically stored in a 32-bit integer can result in significant attempted out-of-bounds reads. (CVE-2024-31080)

- A heap-based buffer over-read vulnerability was found in the X.org server's ProcXIPassiveGrabDevice() function. This issue occurs when byte-swapped length values are used in replies, potentially leading to memory leakage and segmentation faults, particularly when triggered by a client with a different endianness. This vulnerability could be exploited by an attacker to cause the X server to read heap memory values and then transmit them back to the client until encountering an unmapped page, resulting in a crash. Despite the attacker's inability to control the specific memory copied into the replies, the small length values typically stored in a 32-bit integer can result in significant attempted out-of-bounds reads. (CVE-2024-31081)

- A heap-based buffer over-read vulnerability was found in the X.org server's ProcAppleDRICreatePixmap() function. This issue occurs when byte-swapped length values are used in replies, potentially leading to memory leakage and segmentation faults, particularly when triggered by a client with a different endianness. This vulnerability could be exploited by an attacker to cause the X server to read heap memory values and then transmit them back to the client until encountering an unmapped page, resulting in a crash. Despite the attacker's inability to control the specific memory copied into the replies, the small length values typically stored in a 32-bit integer can result in significant attempted out-of-bounds reads. (CVE-2024-31082)

- The X.Org project reports: The ProcXIGetSelectedEvents() function uses the byte-swapped length of the return data for the amount of data to return to the client, if the client has a different endianness than the X server. The ProcXIPassiveGrabDevice() function uses the byte-swapped length of the return data for the amount of data to return to the client, if the client has a different endianness than the X server. The ProcRenderAddGlyphs() function calls the AllocateGlyph() function to store new glyphs sent by the client to the X server. AllocateGlyph() would return a new glyph with refcount=0 and a re-used glyph would end up not changing the refcount at all. The resulting glyph_new array would thus have multiple entries pointing to the same non-refcounted glyphs.
ProcRenderAddGlyphs() may free a glyph, resulting in a use-after-free when the same glyph pointer is then later used. (CVE-2024-31083)

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

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-6721-1

Plugin Details

Severity: High

ID: 192938

File Name: ubuntu_USN-6721-1.nasl

Version: 1.1

Type: local

Agent: unix

Published: 4/5/2024

Updated: 4/8/2024

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2024-31083

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

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

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:xnest, p-cpe:/a:canonical:ubuntu_linux:xorg-server-source, p-cpe:/a:canonical:ubuntu_linux:xserver-common, p-cpe:/a:canonical:ubuntu_linux:xserver-xephyr, p-cpe:/a:canonical:ubuntu_linux:xserver-xorg-core, p-cpe:/a:canonical:ubuntu_linux:xserver-xorg-dev, p-cpe:/a:canonical:ubuntu_linux:xserver-xorg-legacy, p-cpe:/a:canonical:ubuntu_linux:xserver-xorg-xmir, cpe:/o:canonical:ubuntu_linux:14.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:23.10, p-cpe:/a:canonical:ubuntu_linux:xdmx, p-cpe:/a:canonical:ubuntu_linux:xdmx-tools, p-cpe:/a:canonical:ubuntu_linux:xmir, p-cpe:/a:canonical:ubuntu_linux:xvfb, p-cpe:/a:canonical:ubuntu_linux:xwayland

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/4/2024

Vulnerability Publication Date: 4/4/2024

Reference Information

CVE: CVE-2024-31080, CVE-2024-31081, CVE-2024-31082, CVE-2024-31083

USN: 6721-1