#VU70484 Out-of-bounds read in Linux kernel - CVE-2022-47943

Vulnerability identifier: #VU70484

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-47943

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a remote user to perform a denial of service attack.

The vulnerability exists due to an out-of-bounds read in ksmbd due to a large length in the zero DataOffset case in SMB2_WRITE call. A remote user can send specially crafted request to the ksmbd daemon, trigger an out-of-bounds write error and perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: before 5.19.2, 5.19.2

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External links
https://github.com/torvalds/linux/commit/ac60778b87e45576d7bfdbd6f53df902654e6f09
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ac60778b87e45576d7bfdbd6f53df902654e6f09
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.19.2
https://www.openwall.com/lists/oss-security/2022/12/23/10

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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.