CVE-2026-90393
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix potential UAF in bpf_netns_link_update_prog In bpf_netns_link_update_prog, the checks for old_prog and prog type are currently performed locklessly before acquiring netns_bpf_mutex. This creates a race condition that can lead to a UAF issue. If two threads concurrently execute BPF_LINK_UPDATE on the same netns link, the following execution path can trigger a UAF: CPU0 CPU1 bpf_netns_link_update_prog if (old_prog && old_prog != link->prog) return -EPERM; bpf_netns_link_update_prog if (old_prog && old_prog != link->prog) ... old_prog = xchg(&link->prog, new_prog); bpf_prog_put(old_prog); if (new_prog->type != link->prog->type) <-- trigger UAF Fix this by moving the old_prog and prog->type checks inside the netns_bpf_mutex critical section. Meanwhile, use guard() to simplify lock management and avoid all the goto jumping.
View original CVE JSON
{
"id": "CVE-2026-90393",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:17:38.903",
"lastModified": "2026-10-19T09:19:33.373",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix potential UAF in bpf_netns_link_update_prog\n\nIn bpf_netns_link_update_prog, the checks for old_prog and prog type\nare currently performed locklessly before acquiring netns_bpf_mutex.\nThis creates a race condition that can lead to a UAF issue.\n\nIf two threads concurrently execute BPF_LINK_UPDATE on the same netns\nlink, the following execution path can trigger a UAF:\n\nCPU0 CPU1\nbpf_netns_link_update_prog\n if (old_prog && old_prog != link->prog)\n return -EPERM;\n bpf_netns_link_update_prog\n if (old_prog && old_prog != link->prog)\n ...\n old_prog = xchg(&link->prog, new_prog);\n bpf_prog_put(old_prog);\n if (new_prog->type != link->prog->type) <-- trigger UAF\n\nFix this by moving the old_prog and prog->type checks inside the\nnetns_bpf_mutex critical section. Meanwhile, use guard() to simplify\nlock management and avoid all the goto jumping."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/bpf/net_namespace.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "d462b5481d77ce7df8a5ff89a699386f00c9214d",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "bdddf3e1493ee973619c154a57071ce67f78598b",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "79a66fd997d4eecf17302d613194879eb32e0986",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "f4ce6803df4095777191d800bebc50219b615ca0",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "277168cb9d153ce8e9c3f9275670e32ae61b41d6",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "bda86e9f31b9a296b6e64a51c91dc776fc9f613e",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "923f559e95b89b33c7e1793b3d8f7f4ec9b2e4b7",
"versionType": "git",
"status": "affected"
},
{
"version": "7f045a49fee04b5662cbdeaf0838f9322ae8c63a",
"lessThan": "5c5997836381010fc5907b36bc17d3b19407e933",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/bpf/net_namespace.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.8",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.8",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.270",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.221",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.188",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.157",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.110",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.52",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.6",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/277168cb9d153ce8e9c3f9275670e32ae61b41d6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5c5997836381010fc5907b36bc17d3b19407e933",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/79a66fd997d4eecf17302d613194879eb32e0986",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/923f559e95b89b33c7e1793b3d8f7f4ec9b2e4b7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/bda86e9f31b9a296b6e64a51c91dc776fc9f613e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/bdddf3e1493ee973619c154a57071ce67f78598b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d462b5481d77ce7df8a5ff89a699386f00c9214d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f4ce6803df4095777191d800bebc50219b615ca0",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}