Ubuntu Security Notice 6797-1 - It was discovered that some 3rd and 4th Generation Intel® Xeon® Processors did not properly restrict access to certain hardware features when using Intel® SGX or Intel® TDX. This may allow a privileged local user to potentially further escalate their privileges on the system. This issue only affected Ubuntu 23.10, Ubuntu 22.04 LTS, Ubuntu 20.04 LTS, Ubuntu 18.04 LTS and Ubuntu 16.04 LTS. It was discovered that some Intel® Atom® Processors did not properly clear register state when performing various operations. A local attacker could use this to obtain sensitive information via a transient execution attack. This issue only affected Ubuntu 23.10, Ubuntu 22.04 LTS, Ubuntu 20.04 LTS, Ubuntu 18.04 LTS and Ubuntu 16.04 LTS.

Debian Linux Security Advisory 5658-1 - Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.

There are a few reasons why we’re so ready to jump to the “it’s a cyber attack!”

Ubuntu Security Notice 6652-1 - Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service. Zheng Wang discovered a use-after-free in the Renesas Ethernet AVB driver in the Linux kernel during device removal. A privileged attacker could use this to cause a denial of service.

Ubuntu Security Notice 6625-3 - Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service. Zheng Wang discovered a use-after-free in the Renesas Ethernet AVB driver in the Linux kernel during device removal. A privileged attacker could use this to cause a denial of service.

Ubuntu Security Notice 6626-3 - Quentin Minster discovered that a race condition existed in the KSMBD implementation in the Linux kernel when handling sessions operations. A remote attacker could use this to cause a denial of service or possibly execute arbitrary code. Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service.

Ubuntu Security Notice 6628-2 - Quentin Minster discovered that a race condition existed in the KSMBD implementation in the Linux kernel when handling sessions operations. A remote attacker could use this to cause a denial of service or possibly execute arbitrary code. Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service.

Ubuntu Security Notice 6626-2 - Quentin Minster discovered that a race condition existed in the KSMBD implementation in the Linux kernel when handling sessions operations. A remote attacker could use this to cause a denial of service or possibly execute arbitrary code. Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service.

Ubuntu Security Notice 6628-1 - Quentin Minster discovered that a race condition existed in the KSMBD implementation in the Linux kernel when handling sessions operations. A remote attacker could use this to cause a denial of service or possibly execute arbitrary code. Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service.

Ubuntu Security Notice 6626-1 - Quentin Minster discovered that a race condition existed in the KSMBD implementation in the Linux kernel when handling sessions operations. A remote attacker could use this to cause a denial of service or possibly execute arbitrary code. Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service.

Ubuntu Security Notice 6625-1 - Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service. Zheng Wang discovered a use-after-free in the Renesas Ethernet AVB driver in the Linux kernel during device removal. A privileged attacker could use this to cause a denial of service.

Ubuntu Security Notice 6624-1 - Marek Marczykowski-Górecki discovered that the Xen event channel infrastructure implementation in the Linux kernel contained a race condition. An attacker in a guest VM could possibly use this to cause a denial of service. Zheng Wang discovered a use-after-free in the Renesas Ethernet AVB driver in the Linux kernel during device removal. A privileged attacker could use this to cause a denial of service.

Debian Linux Security Advisory 5594-1 - Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.

Cortex-A77 cores (r0p0 and r1p0) are affected by erratum 1508412 where software, under certain circumstances, could deadlock a core due to the execution of either a load to device or non-cacheable memory, and either a store exclusive or register read of the Physical Address Register (PAR_EL1) in close proximity.

An attacker with local access to a system (either through a disk or external drive) can present a modified XFS partition to grub-legacy in such a way to exploit a memory corruption in grub’s XFS file system implementation.

An attacker with local access to a system (either through a disk or external drive) can present a modified XFS partition to grub-legacy in such a way to exploit a memory corruption in grub’s XFS file system implementation.

Ubuntu Security Notice 6441-3 - Ross Lagerwall discovered that the Xen netback backend driver in the Linux kernel did not properly handle certain unusual packets from a paravirtualized network frontend, leading to a buffer overflow. An attacker in a guest VM could use this to cause a denial of service or possibly execute arbitrary code. Kyle Zeng discovered that the networking stack implementation in the Linux kernel did not properly validate skb object size in certain conditions. An attacker could use this cause a denial of service or possibly execute arbitrary code.

Ubuntu Security Notice 6441-2 - Ross Lagerwall discovered that the Xen netback backend driver in the Linux kernel did not properly handle certain unusual packets from a paravirtualized network frontend, leading to a buffer overflow. An attacker in a guest VM could use this to cause a denial of service or possibly execute arbitrary code. Kyle Zeng discovered that the networking stack implementation in the Linux kernel did not properly validate skb object size in certain conditions. An attacker could use this cause a denial of service or possibly execute arbitrary code.

Ubuntu Security Notice 6440-2 - Seth Jenkins discovered that the Linux kernel did not properly perform address randomization for a per-cpu memory management structure. A local attacker could use this to expose sensitive information or in conjunction with another kernel vulnerability. It was discovered that the IPv6 implementation in the Linux kernel contained a high rate of hash collisions in connection lookup table. A remote attacker could use this to cause a denial of service.

Ubuntu Security Notice 6440-1 - Seth Jenkins discovered that the Linux kernel did not properly perform address randomization for a per-cpu memory management structure. A local attacker could use this to expose sensitive information or in conjunction with another kernel vulnerability. It was discovered that the IPv6 implementation in the Linux kernel contained a high rate of hash collisions in connection lookup table. A remote attacker could use this to cause a denial of service.

Ubuntu Security Notice 6442-1 - Ross Lagerwall discovered that the Xen netback backend driver in the Linux kernel did not properly handle certain unusual packets from a paravirtualized network frontend, leading to a buffer overflow. An attacker in a guest VM could use this to cause a denial of service or possibly execute arbitrary code. It was discovered that the netfilter subsystem in the Linux kernel did not properly handle PIPAPO element removal, leading to a use-after-free vulnerability. A local attacker could possibly use this to cause a denial of service or execute arbitrary code.

Ubuntu Security Notice 6441-1 - Ross Lagerwall discovered that the Xen netback backend driver in the Linux kernel did not properly handle certain unusual packets from a paravirtualized network frontend, leading to a buffer overflow. An attacker in a guest VM could use this to cause a denial of service or possibly execute arbitrary code. Kyle Zeng discovered that the networking stack implementation in the Linux kernel did not properly validate skb object size in certain conditions. An attacker could use this cause a denial of service or possibly execute arbitrary code.

Ubuntu Security Notice 6439-1 - It was discovered that the IPv6 implementation in the Linux kernel contained a high rate of hash collisions in connection lookup table. A remote attacker could use this to cause a denial of service. Yu Hao and Weiteng Chen discovered that the Bluetooth HCI UART driver in the Linux kernel contained a race condition, leading to a null pointer dereference vulnerability. A local attacker could use this to cause a denial of service.

The fix for XSA-423 added logic to Linux'es netback driver to deal with a frontend splitting a packet in a way such that not all of the headers would come in one piece. Unfortunately the logic introduced there didn't account for the extreme case of the entire packet being split into as many pieces as permitted by the protocol, yet still being smaller than the area that's specially dealt with to keep all (possible) headers together. Such an unusual packet would therefore trigger a buffer overrun in the driver.

The fix for XSA-423 added logic to Linux'es netback driver to deal with a frontend splitting a packet in a way such that not all of the headers would come in one piece. Unfortunately the logic introduced there didn't account for the extreme case of the entire packet being split into as many pieces as permitted by the protocol, yet still being smaller than the area that's specially dealt with to keep all (possible) headers together. Such an unusual packet would therefore trigger a buffer overrun in the driver.

The fix for XSA-423 added logic to Linux'es netback driver to deal with a frontend splitting a packet in a way such that not all of the headers would come in one piece. Unfortunately the logic introduced there didn't account for the extreme case of the entire packet being split into as many pieces as permitted by the protocol, yet still being smaller than the area that's specially dealt with to keep all (possible) headers together. Such an unusual packet would therefore trigger a buffer overrun in the driver.

Debian Linux Security Advisory 5480-1 - Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.

The AdSanity plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'ajax_upload' function in versions up to, and including, 1.8.1. This makes it possible for authenticated attackers with Contributor+ level privileges to upload arbitrary files on the affected sites server which makes remote code execution possible.

Mishandling of guest SSBD selection on AMD hardware The current logic to set SSBD on AMD Family 17h and Hygon Family 18h processors requires that the setting of SSBD is coordinated at a core level, as the setting is shared between threads. Logic was introduced to keep track of how many threads require SSBD active in order to coordinate it, such logic relies on using a per-core counter of threads that have SSBD active. When running on the mentioned hardware, it's possible for a guest to under or overflow the thread counter, because each write to VIRT_SPEC_CTRL.SSBD by the guest gets propagated to the helper that does the per-core active accounting. Underflowing the counter causes the value to get saturated, and thus attempts for guests running on the same core to set SSBD won't have effect because the hypervisor assumes it's already active.