{"cve":"CVE-2022-50073","nvd":{"published":"2025-06-18T11:15:36.173","modified":"2026-08-12T19:17:26.990","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null\n\nFixes a NULL pointer derefence bug triggered from tap driver.\nWhen tap_get_user calls virtio_net_hdr_to_skb the skb->dev is null\n(in tap.c skb->dev is set after the call to virtio_net_hdr_to_skb)\nvirtio_net_hdr_to_skb calls dev_parse_header_protocol which\nneeds skb->dev field to be valid.\n\nThe line that trigers the bug is in dev_parse_header_protocol\n(dev is at offset 0x10 from skb and is stored in RAX register)\n  if (!dev->header_ops || !dev->header_ops->parse_protocol)\n  22e1:   mov    0x10(%rbx),%rax\n  22e5:\t  mov    0x230(%rax),%rax\n\nSetting skb->dev before the call in tap.c fixes the issue.\n\nBUG: kernel NULL pointer dereference, address: 0000000000000230\nRIP: 0010:virtio_net_hdr_to_skb.constprop.0+0x335/0x410 [tap]\nCode: c0 0f 85 b7 fd ff ff eb d4 41 39 c6 77 cf 29 c6 48 89 df 44 01 f6 e8 7a 79 83 c1 48 85 c0 0f 85 d9 fd ff ff eb b7 48 8b 43 10 <48> 8b 80 30 02 00 00 48 85 c0 74 55 48 8b 40 28 48 85 c0 74 4c 48\nRSP: 0018:ffffc90005c27c38 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: ffff888298f25300 RCX: 0000000000000010\nRDX: 0000000000000005 RSI: ffffc90005c27cb6 RDI: ffff888298f25300\nRBP: ffffc90005c27c80 R08: 00000000ffffffea R09: 00000000000007e8\nR10: ffff88858ec77458 R11: 0000000000000000 R12: 0000000000000001\nR13: 0000000000000014 R14: ffffc90005c27e08 R15: ffffc90005c27cb6\nFS:  0000000000000000(0000) GS:ffff88858ec40000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000000230 CR3: 0000000281408006 CR4: 00000000003706e0\nCall Trace:\n tap_get_user+0x3f1/0x540 [tap]\n tap_sendmsg+0x56/0x362 [tap]\n ? get_tx_bufs+0xc2/0x1e0 [vhost_net]\n handle_tx_copy+0x114/0x670 [vhost_net]\n handle_tx+0xb0/0xe0 [vhost_net]\n handle_tx_kick+0x15/0x20 [vhost_net]\n vhost_worker+0x7b/0xc0 [vhost]\n ? vhost_vring_call_reset+0x40/0x40 [vhost]\n kthread+0xfa/0x120\n ? kthread_complete_and_exit+0x20/0x20\n ret_from_fork+0x1f/0x30","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/447ba770cfe798925f4923548b367fd49f0ee5f0","https://git.kernel.org/stable/c/4f61f133f354853bc394ec7d6028adb9b02dd701","https://git.kernel.org/stable/c/8f90163f9e013c8fc791aab338aab44a46044cfc","https://git.kernel.org/stable/c/dd29648fcf69339713f2d25f7014ae905dcdfc18","http://www.openwall.com/lists/oss-security/2026/08/12/20"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:03:23.287444849+00:00"},"epss":{"cve":"CVE-2022-50073","score":0.00206,"percentile":0.10607,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}