{
  "threat_severity" : "Low",
  "public_date" : "2025-12-30T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: bpf: prevent decl_tag from being referenced in func_proto",
    "id" : "2426043",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2426043"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-1287",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nbpf: prevent decl_tag from being referenced in func_proto\nSyzkaller was able to hit the following issue:\n------------[ cut here ]------------\nWARNING: CPU: 0 PID: 3609 at kernel/bpf/btf.c:1946\nbtf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946\nModules linked in:\nCPU: 0 PID: 3609 Comm: syz-executor361 Not tainted\n6.0.0-syzkaller-02734-g0326074ff465 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS\nGoogle 09/22/2022\nRIP: 0010:btf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946\nCode: ef e8 7f 8e e4 ff 41 83 ff 0b 77 28 f6 44 24 10 18 75 3f e8 6d 91\ne4 ff 44 89 fe bf 0e 00 00 00 e8 20 8e e4 ff e8 5b 91 e4 ff <0f> 0b 45\n31 f6 e9 98 02 00 00 41 83 ff 12 74 18 e8 46 91 e4 ff 44\nRSP: 0018:ffffc90003cefb40 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000\nRDX: ffff8880259c0000 RSI: ffffffff81968415 RDI: 0000000000000005\nRBP: ffff88801270ca00 R08: 0000000000000005 R09: 000000000000000e\nR10: 0000000000000011 R11: 0000000000000000 R12: 0000000000000000\nR13: 0000000000000011 R14: ffff888026ee6424 R15: 0000000000000011\nFS:  000055555641b300(0000) GS:ffff8880b9a00000(0000)\nknlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000f2e258 CR3: 000000007110e000 CR4: 00000000003506f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n<TASK>\nbtf_func_proto_check kernel/bpf/btf.c:4447 [inline]\nbtf_check_all_types kernel/bpf/btf.c:4723 [inline]\nbtf_parse_type_sec kernel/bpf/btf.c:4752 [inline]\nbtf_parse kernel/bpf/btf.c:5026 [inline]\nbtf_new_fd+0x1926/0x1e70 kernel/bpf/btf.c:6892\nbpf_btf_load kernel/bpf/syscall.c:4324 [inline]\n__sys_bpf+0xb7d/0x4cf0 kernel/bpf/syscall.c:5010\n__do_sys_bpf kernel/bpf/syscall.c:5069 [inline]\n__se_sys_bpf kernel/bpf/syscall.c:5067 [inline]\n__x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:5067\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\nRIP: 0033:0x7f0fbae41c69\nCode: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89\nf7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01\nf0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007ffc8aeb6228 EFLAGS: 00000246 ORIG_RAX: 0000000000000141\nRAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0fbae41c69\nRDX: 0000000000000020 RSI: 0000000020000140 RDI: 0000000000000012\nRBP: 00007f0fbae05e10 R08: 0000000000000000 R09: 0000000000000000\nR10: 00000000ffffffff R11: 0000000000000246 R12: 00007f0fbae05ea0\nR13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\n</TASK>\nLooks like it tries to create a func_proto which return type is\ndecl_tag. For the details, see Martin's spot on analysis in [0].\n0: https://lore.kernel.org/bpf/CAKH8qBuQDLva_hHxxBuZzyAcYNO4ejhovz6TQeVSk8HY-2SO6g@mail.gmail.com/T/#mea6524b3fcd6298347432226e81b1e6155efc62c", "A flaw was found in the Linux kernel's BPF BTF (BPF Type Format) validation. The BTF parser allows a func_proto type to reference a decl_tag as its return type, which is invalid. When btf_type_id_size() encounters this unexpected type, it triggers a kernel warning. This can be exploited via the bpf() syscall to cause denial of service." ],
  "statement" : "Loading BPF programs typically requires CAP_BPF or CAP_SYS_ADMIN capabilities in modern kernels, which limits exploitation to privileged users. The flaw results in a kernel warning rather than a crash in most configurations, though repeated triggering could impact system stability.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2022-50862\nhttps://nvd.nist.gov/vuln/detail/CVE-2022-50862\nhttps://lore.kernel.org/linux-cve-announce/2025123048-CVE-2022-50862-124f@gregkh/T" ],
  "name" : "CVE-2022-50862",
  "csaw" : false
}