CVE-2026-22991: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: libceph: make free_choose_arg_map() resilient to partial allocation free_choose_arg_map() may dereference a NULL pointer if its caller fails after a partial allocation. For example, in decode_choose_args(), if allocation of arg_map->args fails, execution jumps to the fail label and free_choose_arg_map() is called. Since arg_map->size is updated to a non-zero value before memory allocation, free_choose_arg_map() will iterate over arg_map->args and dereference a NULL pointer. To prevent this potential NULL pointer dereference and make free_choose_arg_map() more resilient, add checks for pointers before iterating.

Affected products

• Linux Linux Kernel: from 4.13, before 5.10.248 (fixed in 5.10.248); from 5.11, before 5.15.198 (fixed in 5.15.198); from 5.16, before 6.1.161 (fixed in 6.1.161); from 6.2, before 6.6.121 (fixed in 6.6.121); from 6.7, before 6.12.66 (fixed in 6.12.66); from 6.13, before 6.18.6 (fixed in 6.18.6); …

Published 2026-01-23. Last modified 2026-06-17.