CVE-2026-64113 ixgbevf: fix use-after-free in VEPA multicast source pruning
A use-after-free in the ixgbevf kernel driver allows attackers to cause denial of service or potentially execute code via crafted network traffic.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64113?
CVE-2026-64113 is a critical use after free vulnerability in Linux kernel, published on 19 Jul 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:
ixgbevf: fix use-after-free in VEPA multicast source pruning
ixgbevf_clean_rx_irq() prunes frames whose source MAC matches the VF's own address (VEPA multicast workaround) by freeing the skb and continuing to the next descriptor:
dev_kfree_skb_irq(skb); continue;
The skb pointer is declared outside the while loop and persists across iterations. Because the continue skips the "skb = NULL" reset at the bottom of the loop, the next iteration enters the "else if (skb)" path and calls ixgbevf_add_rx_frag() on the freed skb, dereferencing skb_shinfo(skb)->nr_frags - a use-after-free in NAPI softirq context.
The sibling driver iavf already handles this correctly by nulling the pointer before continuing. Apply the same pattern here.
I do not have ixgbevf hardware; the bug was found by static analysis (scan_drop_continue_loops.py + semgrep drop_continue_in_loop, multi-tool corroboration with the highest score in the scan). The UAF was confirmed under KASAN by loading a test module that reproduces the exact code pattern (alloc skb, kfree_skb, then read skb_shinfo(skb)->nr_frags):
BUG: KASAN: slab-use-after-free in ixgbevf_uaf_test_init+0x100/0x1000 Read of size 8 at addr 000000006163ae78 by task insmod/30 freed 208-byte region [000000006163adc0, 000000006163ae90)
QEMU emulates igb (82576) but not ixgbe (82599), and the igbvf VF driver does not include the VEPA source pruning path, so a full end-to-end reproduction with emulated hardware was not possible.
Weakness: CWE-416
Which versions are affected by CVE-2026-64113?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-64113?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-64113 being exploited?
There is no known exploitation of CVE-2026-64113 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-64113, DEBIAN-CVE-2026-64113, GHSA-gwhj-73cj-phr2, UBUNTU-CVE-2026-64113.