A libgcrypt security update has been released for Arch Linux.

Arch Linux Security Advisory ASA-202101-45
==========================================

Severity: Critical
Date : 2021-01-29
CVE-ID : CVE-2021-3345
Package : libgcrypt
Type : arbitrary code execution
Remote : No
Link :   https://security.archlinux.org/AVG-1505

Summary
=======

The package libgcrypt before version 1.9.1-1 is vulnerable to arbitrary
code execution.

Resolution
==========

Upgrade to 1.9.1-1.

# pacman -Syu "libgcrypt>=1.9.1-1"

The problem has been fixed upstream in version 1.9.1.

Workaround
==========

None.

Description
===========

_gcry_md_block_write in cipher/hash-common.c in libgcrypt version 1.9.0
has a heap-based buffer overflow when the digest final function sets a
large count value. Just decrypting some data can overflow a heap buffer
with attacker controlled data, no verification or signature is
validated before the vulnerability occurs. The issue is fixed in
version 1.9.1.

Impact
======

An attacker is able to execute arbitrary code on the affected host
before a given signature has been verified.

References
==========

  https://lists.gnupg.org/pipermail/gnupg-announce/2021q1/000456.html
  https://dev.gnupg.org/T5275
  https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commitdiff;h=512c0c75276949f13b6373b5c04f7065af750b08
  https://security.archlinux.org/CVE-2021-3345