Arch Linux alert ASA-202007-6 (libjcat)

From:
             
 
Morten Linderud <foxboron@archlinux.org> 
To:
             
 
arch-security@archlinux.org 
Subject:
             
 
[ASA-202007-6] libjcat: insufficient validation 
Date:
             
 
Fri, 31 Jul 2020 22:03:06 +0200
Message-ID:
             
 
<20200731200306.imcpwxhocrmgnnqb@anathema>
Arch Linux Security Advisory ASA-202007-6
=========================================

Severity: High
Date    : 2020-07-31
CVE-ID  : CVE-2020-10759
Package : libjcat
Type    : insufficient validation
Remote  : Yes
Link    : https://security.archlinux.org/AVG-1185

Summary
=======

The package libjcat before version 0.1.3-1 is vulnerable to
insufficient validation.

Resolution
==========

Upgrade to 0.1.3-1.

# pacman -Syu "libjcat>=0.1.3-1"

The problem has been fixed upstream in version 0.1.3.

Workaround
==========

None.

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

A PGP signature verification bypass has been found in fwupd prior to
1.4.0, and in libjcat <= 0.1.2. The issue is that if a detached
signature is actually a PGP message, gpgme_op_verify() returns the
rather perplexing GPG_ERR_NO_ERROR, and then gpgme_op_verify_result()
builds an empty list.

Impact
======

A local attacker could pass signature validation with a crafted
message.

References
==========

https://github.com/justinsteven/advisories/blob/master/20...
https://github.com/hughsie/libjcat/commit/839b89f
https://security.archlinux.org/CVE-2020-10759