Use-after-free in Linux kernel ksmbd

1) Use-after-free

EUVDB-ID: #VU90249

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-2023-52480

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

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 ksmbd_expire_session(), ksmbd_sessions_deregister() and ksmbd_session_lookup() functions in fs/ksmbd/mgmt/user_session.c, within the ksmbd_conn_alloc() function in fs/ksmbd/connection.c. A local user can escalate privileges on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:*:*:*:*:*:*:*:*

External links

https://git.kernel.org/stable/c/c77fd3e25a51ac92b0f1b347a96eff6a0b4f066f
https://git.kernel.org/stable/c/a2ca5fd3dbcc665e1169044fa0c9e3eba779202b
https://git.kernel.org/stable/c/18ced78b0ebccc2d16f426143dc56ab3aad666be
https://git.kernel.org/stable/c/53ff5cf89142b978b1a5ca8dc4d4425e6a09745f

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.