Vulnerability identifier: #VU59474

Vulnerability risk: Low

CVSSv3.1: 5.8 [CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-42739

CWE-ID: CWE-119

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor:

Description

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

The vulnerability exists due to a boundary within the firewire subsystem in the Linux kernel in drivers/media/firewire/firedtv-avc.c and drivers/media/firewire/firedtv-ci.c files. A local privileged user can run a specially crafted program tat calls avc_ca_pmt() function to trigger memory corruption and execute arbitrary code with elevated privileges.

Mitigation
Install update from vendor's website.

Vulnerable software versions

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External links
http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=35d2969ea3c7d32aee78066b1f3cf61a0d935a4e
http://seclists.org/oss-sec/2021/q2/46
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6EHZNHNHRLPC2NJKUDS5PJG5AGRYJVJN/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AOWGMZ2MJFUGNA5QSD5JF4QHIC4URATS/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CKMQEOEESIO3GMHAOL3NYS36FER6UTWA/
http://security.netapp.com/advisory/ntap-20211118-0001/
http://lists.debian.org/debian-lts-announce/2021/12/msg00012.html

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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