GHSA-PG7W-XRHC-WHGH
Vulnerability from github – Published: 2026-08-05 09:31 – Updated: 2026-08-05 09:31In the Linux kernel, the following vulnerability has been resolved:
nexthop: initialize extack in nh_res_bucket_migrate()
nh_res_bucket_migrate() passes an uninitialized netlink_ext_ack to call_nexthop_res_bucket_notifiers(). When nh_notifier_res_bucket_info_init() fails (e.g. the kzalloc returns -ENOMEM), the error is propagated back before any notifier sets extack._msg, and the error path formats the stale pointer with pr_err_ratelimited("%s\n", extack._msg). With CONFIG_INIT_STACK_NONE this dereferences uninitialized stack memory:
Oops: general protection fault, probably for non-canonical address ... KASAN: maybe wild-memory-access in range [...] RIP: 0010:string (lib/vsprintf.c:730) vsnprintf (lib/vsprintf.c:2945) _printk (kernel/printk/printk.c:2504) nh_res_bucket_migrate (net/ipv4/nexthop.c:1816) nh_res_table_upkeep (net/ipv4/nexthop.c:1866) rtm_new_nexthop (net/ipv4/nexthop.c:3323) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) netlink_sendmsg (net/netlink/af_netlink.c:1900) Kernel panic - not syncing: Fatal exception
Zero-initialize extack so _msg is NULL on error paths that never set it.
{
"affected": [],
"aliases": [
"CVE-2026-64576"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-05T08:16:37Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnexthop: initialize extack in nh_res_bucket_migrate()\n\nnh_res_bucket_migrate() passes an uninitialized netlink_ext_ack to\ncall_nexthop_res_bucket_notifiers(). When\nnh_notifier_res_bucket_info_init() fails (e.g. the kzalloc returns\n-ENOMEM), the error is propagated back before any notifier sets\nextack._msg, and the error path formats the stale pointer with\npr_err_ratelimited(\"%s\\n\", extack._msg). With CONFIG_INIT_STACK_NONE\nthis dereferences uninitialized stack memory:\n\n Oops: general protection fault, probably for non-canonical address ...\n KASAN: maybe wild-memory-access in range [...]\n RIP: 0010:string (lib/vsprintf.c:730)\n vsnprintf (lib/vsprintf.c:2945)\n _printk (kernel/printk/printk.c:2504)\n nh_res_bucket_migrate (net/ipv4/nexthop.c:1816)\n nh_res_table_upkeep (net/ipv4/nexthop.c:1866)\n rtm_new_nexthop (net/ipv4/nexthop.c:3323)\n rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)\n netlink_sendmsg (net/netlink/af_netlink.c:1900)\n Kernel panic - not syncing: Fatal exception\n\nZero-initialize extack so _msg is NULL on error paths that never set it.",
"id": "GHSA-pg7w-xrhc-whgh",
"modified": "2026-08-05T09:31:17Z",
"published": "2026-08-05T09:31:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64576"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/18506d7263768d76ac8e057ba55a4d9da50aad66"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3081702ea5aca0aeed9c1ade8eadf6cde8db6b7d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6347c5314cee49f364aaf2e40ff15415a57a116e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c0936c131a71657afc635d0db2ab096d15d473e1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d536bf205c71f700f6de2086038c3e1d77724715"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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