Out-of-bounds read in Linux kernel

1) Out-of-bounds read

EUVDB-ID: #VU81661

Risk: Medium

CVSSv3.1: 4.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-3865

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 or perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary condition within the ksmbd_smb2_check_message() function in fs/smb/server/smb2misc.c when parsing smb2_hdr structure. A remote user can send specially crafted packets to ksmbd, trigger an out-of-bounds read error and read contents of memory or perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

CPE2.3

External links

http://www.zerodayinitiative.com/advisories/ZDI-23-980/
http://lore.kernel.org/all/20230626180806.056931954@linuxfoundation.org/
http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5fe7f7b78290638806211046a99f031ff26164e1

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.