CVE-2026-43107

Summary

In the Linux kernel, the following vulnerability has been resolved:

xfrm: account XFRMA_IF_ID in aevent size calculation

xfrm_get_ae() allocates the reply skb with xfrm_aevent_msgsize(), then build_aevent() appends attributes including XFRMA_IF_ID when x->if_id is set.

xfrm_aevent_msgsize() does not include space for XFRMA_IF_ID. For states with if_id, build_aevent() can fail with -EMSGSIZE and hit BUG_ON(err < 0) in xfrm_get_ae(), turning a malformed netlink interaction into a kernel panic.

Account XFRMA_IF_ID in the size calculation unconditionally and replace the BUG_ON with normal error unwinding.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux7e6526404adedf079279aa7aa11722deaca8fe2e < 2c41283d94af943a05f7f2cc1a01f0c872f3cf43affected
LinuxLinux7e6526404adedf079279aa7aa11722deaca8fe2e < e62e322ea20be78e346e4b49f9a6b9f03313af4caffected
LinuxLinux7e6526404adedf079279aa7aa11722deaca8fe2e < 58e5735d1a5373652f405a0c16e54ac04aaab0adaffected
LinuxLinux7e6526404adedf079279aa7aa11722deaca8fe2e < 7081d46d32312f1a31f0e0e99c6835a394037599affected
LinuxLinux4.19affected
LinuxLinux0 < 4.19unaffected
LinuxLinux6.12.83 <= 6.12.*unaffected
LinuxLinux6.18.24 <= 6.18.*unaffected
LinuxLinux6.19.14 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References