A libebml security update has been released for Arch Linux.

ASA-202103-18: libebml: arbitrary code execution

Arch Linux Security Advisory ASA-202103-18
=========================================
Severity: High
Date : 2021-03-25
CVE-ID : CVE-2021-3405
Package : libebml
Type : arbitrary code execution
Remote : Yes
Link :   https://security.archlinux.org/AVG-1554

Summary
======
The package libebml before version 1.4.2-1 is vulnerable to arbitrary
code execution.

Resolution
=========
Upgrade to 1.4.2-1.

# pacman -Syu "libebml>=1.4.2-1"

The problem has been fixed upstream in version 1.4.2.

Workaround
=========
None.

Description
==========
A security issue was found in libebml before version 1.4.2. A heap
overflow bug exists in the implementation of EbmlString::ReadData and
EbmlUnicodeString::ReadData in libebml.

Impact
=====
A crafted file could execute arbitrary code.

References
=========
  https://bugs.archlinux.org/task/70039
  https://bugzilla.redhat.com/show_bug.cgi?id26990
  https://github.com/Matroska-Org/libebml/issues/74
  https://github.com/Matroska-Org/libebml/pull/76
  https://github.com/Matroska-Org/libebml/commit/3d3d2cff9b012059fa7cb536399b582cc796e04f
  https://security.archlinux.org/CVE-2021-3405