Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3889
Advisory Released Date: 2026-08-31
Advisory Updated Date: 2026-08-31
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
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update libXfont2 or yum update --advisory ALAS2-2026-3889 to update your system.
aarch64:
libXfont2-2.0.3-1.amzn2.0.2.aarch64
libXfont2-devel-2.0.3-1.amzn2.0.2.aarch64
libXfont2-debuginfo-2.0.3-1.amzn2.0.2.aarch64
i686:
libXfont2-2.0.3-1.amzn2.0.2.i686
libXfont2-devel-2.0.3-1.amzn2.0.2.i686
libXfont2-debuginfo-2.0.3-1.amzn2.0.2.i686
src:
libXfont2-2.0.3-1.amzn2.0.2.src
x86_64:
libXfont2-2.0.3-1.amzn2.0.2.x86_64
libXfont2-devel-2.0.3-1.amzn2.0.2.x86_64
libXfont2-debuginfo-2.0.3-1.amzn2.0.2.x86_64