Denial of service in QEM

1) Out-of-bounds read

EUVDB-ID: #VU50042

Risk: Medium

CVSSv3.1: 5.9 [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-29443

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition within the ide_atapi_cmd_reply_end() function in hw/ide/atapi.c in QEMU. A remote user can create a specially crafted file, trick the victim into opening it, trigger out-of-bounds read error and read contents of memory on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

QEMU: 5.1.0

External links

http://www.openwall.com/lists/oss-security/2021/01/18/2
http://lists.nongnu.org/archive/html/qemu-devel/2020-11/msg04685.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the local network (LAN).

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to open a a specially crafted file.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.