The USN-8391-1 advisory details multiple high-severity local privilege escalation vulnerabilities in the Linux kernel for Raspberry Pi, including the "Copy Fail" flaw in the algif_aead module (CVE-2026-31431, CVSS 7.8) and the "Dirty Frag" logic flaws in XFRM ESP-in-TCP and RxRPC subsystems (CVE-2026-43284, CVSS 8.8; CVE-2026-43500, CVSS 7.8). These vulnerabilities affect a wide range of kernel versions, for example, CVE-2026-31431 affects versions from 4.14 up to but excluding 5.10.254, from 5.11 up to but excluding 5.15.204, and similarly through several major version branches. The fixed versions are specified per CVE and branch, such as upgrading to kernel version 5.10.254, 5.15.204, 6.1.170, or later as applicable to the specific kernel series in use.
It was discovered that the Linux kernel algif_aead module did not properly handle in-place cryptographic operations. This flaw is known as Copy Fail. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-31431) It was discovered that the Linux kernel did not properly handle shared page fragments during socket buffer operations, collectively known as Dirty Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the RxRPC networking subsystem when processing paged fragments. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-43284, CVE-2026-43500) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - Cryptographic API; - Network drivers; - NVME drivers; - IPv4 networking; - Packet sockets; - RDS protocol; - TLS protocol; (CVE-2024-50304, CVE-2026-23112, CVE-2026-23209, CVE-2026-31504, CVE-2026-31533, CVE-2026-43033, CVE-2026-43077, CVE-2026-43078, CVE-2026-43494, CVE-2026-46028)