ALAS2023-2026-2112


Amazon Linux 2023 Security Advisory: ALAS2023-2026-2112
Advisory Released Date: 2026-08-31
Advisory Updated Date: 2026-08-31
Severity: Important

Issue Overview:

A flaw was found in the libXfont2 font-server client. This heap buffer overflow vulnerability allows a malicious font server to send specially crafted glyph data. The fs_read_glyphs() function fails to properly validate the total size of the incoming data, leading to an overwrite of memory beyond the intended buffer. If the X server runs as a privileged user, this could result in privilege escalation, allowing an attacker to gain higher access. If the X server runs as an unprivileged user, it could lead to a denial of service, causing the system to crash. (CVE-2026-44950)

A flaw was found in the libXfont2 font-server client. A remote attacker, by operating a malicious font server, could exploit an out-of-bounds read/write vulnerability. This occurs because the client incorrectly handles font data, leading to an out-of-bounds memory access. This can lead to privilege escalation if the X server runs with root privileges, or a denial of service (crash) if it runs as an unprivileged user. (CVE-2026-59679)


Affected Packages:

libXfont2


Issue Correction:
Run dnf update libXfont2 --releasever 2023.12.20260831 or dnf update --advisory ALAS2023-2026-2112 --releasever 2023.12.20260831 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation

New Packages:
aarch64:
    libXfont2-debugsource-2.0.7-1.amzn2023.0.3.aarch64
    libXfont2-debuginfo-2.0.7-1.amzn2023.0.3.aarch64
    libXfont2-devel-2.0.7-1.amzn2023.0.3.aarch64
    libXfont2-2.0.7-1.amzn2023.0.3.aarch64

src:
    libXfont2-2.0.7-1.amzn2023.0.3.src

x86_64:
    libXfont2-debugsource-2.0.7-1.amzn2023.0.3.x86_64
    libXfont2-debuginfo-2.0.7-1.amzn2023.0.3.x86_64
    libXfont2-devel-2.0.7-1.amzn2023.0.3.x86_64
    libXfont2-2.0.7-1.amzn2023.0.3.x86_64