#VU53681 Out-of-bounds write in QEMU - CVE-2021-3546

Vulnerability identifier: #VU53681

Vulnerability risk: Medium

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3546

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
QEMU
Client/Desktop applications / Virtualization software

Vendor: QEMU

Description

The vulnerability allows a remote user to escalate privileges on the system.

The vulnerability exists due to a boundary error when processing untrusted input within the virgl_cmd_get_capset() function in vhost-user-gpu/virgl.c. A remote authenticated user of the guest operating system can trigger an out-of-bounds write and escalate privileges.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

QEMU: 4.1.0 - 6.0.0

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External links
https://seclists.org/oss-sec/2021/q2/176
https://gitlab.com/qemu-project/qemu/-/commit/9f22893a

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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