GHSA-GWHJ-73CJ-PHR2
Vulnerability from github – Published: 2026-07-19 18:31 – Updated: 2026-07-20 15:32In 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.
{
"affected": [],
"aliases": [
"CVE-2026-64113"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-19T16:17:52Z",
"severity": "CRITICAL"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nixgbevf: fix use-after-free in VEPA multicast source pruning\n\nixgbevf_clean_rx_irq() prunes frames whose source MAC matches the VF\u0027s\nown address (VEPA multicast workaround) by freeing the skb and\ncontinuing to the next descriptor:\n\n dev_kfree_skb_irq(skb);\n continue;\n\nThe skb pointer is declared outside the while loop and persists across\niterations. Because the continue skips the \"skb = NULL\" reset at the\nbottom of the loop, the next iteration enters the \"else if (skb)\" path\nand calls ixgbevf_add_rx_frag() on the freed skb, dereferencing\nskb_shinfo(skb)-\u003enr_frags - a use-after-free in NAPI softirq context.\n\nThe sibling driver iavf already handles this correctly by nulling the\npointer before continuing. Apply the same pattern here.\n\nI do not have ixgbevf hardware; the bug was found by static analysis\n(scan_drop_continue_loops.py + semgrep drop_continue_in_loop, multi-tool\ncorroboration with the highest score in the scan). The UAF was confirmed\nunder KASAN by loading a test module that reproduces the exact code\npattern (alloc skb, kfree_skb, then read skb_shinfo(skb)-\u003enr_frags):\n\n BUG: KASAN: slab-use-after-free in ixgbevf_uaf_test_init+0x100/0x1000\n Read of size 8 at addr 000000006163ae78 by task insmod/30\n freed 208-byte region [000000006163adc0, 000000006163ae90)\n\nQEMU emulates igb (82576) but not ixgbe (82599), and the igbvf VF\ndriver does not include the VEPA source pruning path, so a full\nend-to-end reproduction with emulated hardware was not possible.",
"id": "GHSA-gwhj-73cj-phr2",
"modified": "2026-07-20T15:32:00Z",
"published": "2026-07-19T18:31:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64113"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3d931ac62411a7e43b85dba5fe45e1a4a91bd5cb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/55b3e91d62b2f7a24109b2d7c9f4c66d2e3b1ec1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5d49b568c188dc77199d8d2b959c91da8cc27cf1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6ef30384a50a50e4a484cddf341bc27de31aa3de"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a244395d8c563ed1bb26c3ef708db6aeeaa08084"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/add70e2682c0ad3be2a5810bcf1bc13963ba4df9"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dfef79e09ed2f5df975c98547f97f5d7f8982a24"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e8768bcbe5cd30c4ea36a22022c9ffaa66903693"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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