CVE-2026-90115 xsk: fix NULL pointer dereference in __xsk_rcv()
A NULL pointer dereference in the Linux kernel's XSK receive path allows remote attackers to cause a system crash via crafted network packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90115?
CVE-2026-90115 is a vulnerability in Linux, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
xsk: fix NULL pointer dereference in __xsk_rcv()
In the __xsk_rcv() multi-buffer path, xsk_buff_alloc() is called in a loop without checking its return value. xsk_buff_can_alloc() only counts fill queue entries without validating their addresses, so it can succeed while xsk_buff_alloc() rejects all remaining entries and returns NULL.
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000 KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:__xsk_rcv+0x426/0xc20 (net/xdp/xsk.c:350) Call Trace: xsk_generic_rcv+0x26d/0x5f0 xdp_do_generic_redirect+0x3c5/0xcf0 do_xdp_generic+0x92f/0xe70 __netif_receive_skb_core.constprop.0+0xf7e/0x2b30
Fix this with a two-stage transaction. First allocate and stage all buffers required for the packet, recycling all staged buffers with xsk_buff_free() if any allocation fails. Only after this stage succeeds, copy the data, reserve the RX descriptors, and release the buffers in an error-free loop.
Which versions are affected by CVE-2026-90115?
How do I fix CVE-2026-90115?
Apply the vendor's patch.
Is CVE-2026-90115 being exploited?
There is no known exploitation of CVE-2026-90115 in the wild and no public exploit code.
Sources
Also known as AZL-102068, BELL-CVE-2026-90115, DEBIAN-CVE-2026-90115, GHSA-fwqw-j57j-h6cj, UBUNTU-CVE-2026-90115.