Subject: [ASA-202101-32] linux-hardened: directory traversal

Arch Linux Security Advisory ASA-202101-32
==========================================

Severity: Medium
Date    : 2021-01-20
CVE-ID  : CVE-2020-28374
Package : linux-hardened
Type    : directory traversal
Remote  : No
Link    : https://security.archlinux.org/AVG-1443

Summary
=======

The package linux-hardened before version 5.10.7.a-1 is vulnerable to
directory traversal.

Resolution
==========

Upgrade to 5.10.7.a-1.

# pacman -Syu "linux-hardened>=5.10.7.a-1"

The problem has been fixed upstream in version 5.10.7.a.

Workaround
==========

None.

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

In drivers/target/target_core_xcopy.c in the Linux kernel before
5.10.7, insufficient identifier checking in the LIO SCSI target code
can be used by remote attackers to read or write files via directory
traversal in an XCOPY request, aka CID-2896c93811e3. For example, an
attack can occur over a network if the attacker has access to one iSCSI
LUN. The attacker gains control over file access because I/O operations
are proxied via an attacker-selected backstore.

Impact
======

An attacker can traverse directories on the system through malicious
operations.

References
==========

https://www.openwall.com/lists/oss-security/2021/01/12/12
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v5.10.7&id=6f1e88527c1869de08632efa2cc796e0131850dc
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v5.4.89&id=485e21729b1e1235e6075318225c09e76b376e81
https://security.archlinux.org/CVE-2020-28374