#VU99444 Use-after-free in Linux kernel - CVE-2024-50086

Vulnerability identifier: #VU99444

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2024-50086

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

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

Vendor: Linux Foundation

Description

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

The vulnerability exists due to a use-after-free error within the smb2_check_user_session(), smb2_sess_setup() and smb2_session_logoff() functions in fs/smb/server/smb2pdu.c, within the __handle_ksmbd_work() function in fs/smb/server/server.c, within the ksmbd_expire_session(), ksmbd_session_lookup_slowpath(), ksmbd_session_lookup_all() and __session_create() functions in fs/smb/server/mgmt/user_session.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
http://git.kernel.org/stable/c/a9839c37fd813b432988f58a9d9dd59253d3eb2c
http://git.kernel.org/stable/c/5511999e9615e4318e9142d23b29bd1597befc08
http://git.kernel.org/stable/c/ee371898b53a9b9b51c02d22a8c31bfb86d45f0d
http://git.kernel.org/stable/c/7aa8804c0b67b3cb263a472d17f2cb50d7f1a930

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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.