CVE-2023-32251

A vulnerability has been identified in the Linux kernel's ksmbd component (kernel SMB/CIFS server). A security control designed to prevent dictionary attacks, which introduces a 5-second delay during session setup, can be bypassed through the use of asynchronous requests. This bypass negates the intended anti-brute-force protection, potentially allowing attackers to conduct dictionary attacks more efficiently against user credentials or other authentication mechanisms.

The Linux Kernel, the operating system core itself.

Security Fix(es):

An issue was discovered in the Linux kernel through 6.0.9. drivers/media/usb/ttusb-dec/ttusb_dec.c has a memory leak because of the lack of a dvb_frontend_detach call.(CVE-2022-45887)

A division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality. 

(CVE-2023-20588)

In multiple functions of io_uring.c, there is a possible kernel memory corruption due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.

(CVE-2023-21400)

VUL-0: CVE-2023-32249: kernel: Linux Kernel ksmbd Multichannel Improper Authentication Session Hijack Vulnerability(CVE-2023-32249)

VUL-0: CVE-2023-32251: kernel: Linux Kernel ksmbd Improper Restriction of Excessive Authentication Attempts Protection Bypass Vulnerability(CVE-2023-32251)

VUL-0: CVE-2023-32253: kernel: Linux Kernel ksmbd Session Deadlock Denial-of-Service Vulnerability(CVE-2023-32253)

** REJECT ** CVE-2023-4881 was wrongly assigned to a bug that was deemed to be a non-security issue by the Linux kernel security team.(CVE-2023-4881)

A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.

When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue().

We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.

(CVE-2023-4921)

The Linux Kernel, the operating system core itself.

Security Fix(es):

An issue was discovered in the Linux kernel through 6.0.9. drivers/media/usb/ttusb-dec/ttusb_dec.c has a memory leak because of the lack of a dvb_frontend_detach call.(CVE-2022-45887)

A division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality. 

(CVE-2023-20588)

In multiple functions of io_uring.c, there is a possible kernel memory corruption due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.

(CVE-2023-21400)

VUL-0: CVE-2023-32249: kernel: Linux Kernel ksmbd Multichannel Improper Authentication Session Hijack Vulnerability(CVE-2023-32249)

VUL-0: CVE-2023-32251: kernel: Linux Kernel ksmbd Improper Restriction of Excessive Authentication Attempts Protection Bypass Vulnerability(CVE-2023-32251)

VUL-0: CVE-2023-32253: kernel: Linux Kernel ksmbd Session Deadlock Denial-of-Service Vulnerability(CVE-2023-32253)

** REJECT ** CVE-2023-4881 was wrongly assigned to a bug that was deemed to be a non-security issue by the Linux kernel security team.(CVE-2023-4881)

A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.

When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue().

We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.

(CVE-2023-4921)

The Linux Kernel, the operating system core itself.

Security Fix(es):

An issue was discovered in the Linux kernel through 6.0.9. drivers/media/usb/ttusb-dec/ttusb_dec.c has a memory leak because of the lack of a dvb_frontend_detach call.(CVE-2022-45887)

A division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality. 

(CVE-2023-20588)

In multiple functions of io_uring.c, there is a possible kernel memory corruption due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.

(CVE-2023-21400)

VUL-0: CVE-2023-32249: kernel: Linux Kernel ksmbd Multichannel Improper Authentication Session Hijack Vulnerability(CVE-2023-32249)

VUL-0: CVE-2023-32251: kernel: Linux Kernel ksmbd Improper Restriction of Excessive Authentication Attempts Protection Bypass Vulnerability(CVE-2023-32251)

VUL-0: CVE-2023-32253: kernel: Linux Kernel ksmbd Session Deadlock Denial-of-Service Vulnerability(CVE-2023-32253)

** REJECT ** CVE-2023-4881 was wrongly assigned to a bug that was deemed to be a non-security issue by the Linux kernel security team.(CVE-2023-4881)

A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.

When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue().

We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.

(CVE-2023-4921)

A vulnerability has been identified in the Linux kernel's ksmbd component (kernel SMB/CIFS server). A security control designed to prevent dictionary attacks, which introduces a 5-second delay during session setup, can be bypassed through the use of asynchronous requests. This bypass negates the intended anti-brute-force protection, potentially allowing attackers to conduct dictionary attacks more efficiently against user credentials or other authentication mechanisms.