Vulnerabilities
Misconfiguration
Runtime Security
Compliance
CVE Vulnerabilities

CVE-2023-6377

Out-of-bounds Read

Published: Dec 13, 2023 | Modified: Nov 21, 2024
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
7.8 IMPORTANT
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM
Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2023-6377
CWEhttps://cwe.mitre.org/data/definitions/125.html

A flaw was found in xorg-server. Querying or changing XKB button actions such as moving from a touchpad to a mouse can result in out-of-bounds memory reads and writes. This may allow local privilege escalation or possible remote code execution in cases where X11 forwarding is involved.

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Name Vendor Start Version End Version
Enterprise_linux_eus Redhat 9.2 (including) 9.2 (including)
Red Hat Enterprise Linux 7 RedHat tigervnc-0:1.8.0-28.el7_9 *
Red Hat Enterprise Linux 7 RedHat xorg-x11-server-0:1.20.4-25.el7_9 *
Red Hat Enterprise Linux 8 RedHat tigervnc-0:1.13.1-2.el8_9.4 *
Red Hat Enterprise Linux 8 RedHat xorg-x11-server-0:1.20.11-22.el8 *
Red Hat Enterprise Linux 8 RedHat xorg-x11-server-Xwayland-0:21.1.3-15.el8 *
Red Hat Enterprise Linux 8.2 Advanced Update Support RedHat tigervnc-0:1.9.0-15.el8_2.6 *
Red Hat Enterprise Linux 8.2 Telecommunications Update Service RedHat tigervnc-0:1.9.0-15.el8_2.6 *
Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions RedHat tigervnc-0:1.9.0-15.el8_2.6 *
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support RedHat tigervnc-0:1.11.0-8.el8_4.5 *
Red Hat Enterprise Linux 8.4 Telecommunications Update Service RedHat tigervnc-0:1.11.0-8.el8_4.5 *
Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions RedHat tigervnc-0:1.11.0-8.el8_4.5 *
Red Hat Enterprise Linux 8.6 Extended Update Support RedHat tigervnc-0:1.12.0-6.el8_6.6 *
Red Hat Enterprise Linux 8.8 Extended Update Support RedHat tigervnc-0:1.12.0-15.el8_8.4 *
Red Hat Enterprise Linux 9 RedHat tigervnc-0:1.13.1-3.el9_3.3 *
Red Hat Enterprise Linux 9 RedHat xorg-x11-server-0:1.20.11-24.el9 *
Red Hat Enterprise Linux 9 RedHat xorg-x11-server-Xwayland-0:22.1.9-5.el9 *
Red Hat Enterprise Linux 9.0 Extended Update Support RedHat tigervnc-0:1.11.0-22.el9_0.5 *
Red Hat Enterprise Linux 9.2 Extended Update Support RedHat tigervnc-0:1.12.0-14.el9_2.2 *
Xorg Ubuntu bionic *
Xorg Ubuntu trusty *
Xorg Ubuntu xenial *
Xorg-server Ubuntu bionic *
Xorg-server Ubuntu devel *
Xorg-server Ubuntu esm-infra/bionic *
Xorg-server Ubuntu esm-infra/xenial *
Xorg-server Ubuntu focal *
Xorg-server Ubuntu jammy *
Xorg-server Ubuntu lunar *
Xorg-server Ubuntu mantic *
Xorg-server Ubuntu noble *
Xorg-server Ubuntu oracular *
Xorg-server Ubuntu trusty *
Xorg-server Ubuntu trusty/esm *
Xorg-server Ubuntu upstream *
Xorg-server Ubuntu xenial *
Xorg-server-hwe-16.04 Ubuntu xenial *
Xorg-server-hwe-18.04 Ubuntu bionic *
Xorg-server-lts-utopic Ubuntu trusty *
Xorg-server-lts-vivid Ubuntu trusty *
Xorg-server-lts-wily Ubuntu trusty *
Xorg-server-lts-xenial Ubuntu trusty *
Xwayland Ubuntu jammy *
Xwayland Ubuntu lunar *
Xwayland Ubuntu mantic *
Xwayland Ubuntu upstream *

Potential Mitigations

  • Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
  • To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

References

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