CVE-2022-50073 | net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null

In the Linux kernel, the following vulnerability has been resolved: net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null Fixes a NULL pointer derefence bug triggered from tap driver. When tap_get_user calls virtio_net_hdr_to_skb the skb->dev is null (in tap.c skb->dev is set after the call to virtio_net_hdr_to_skb) virtio_net_hdr_to_skb calls dev_parse_header_protocol which needs skb->dev field to be valid. The line that trigers the bug is in dev_parse_header_protocol (dev is at offset 0x10 from skb and is stored in RAX register) if (!dev->header_ops || !dev->header_ops->parse_protocol) 22e1: mov 0x10(%rbx),%rax 22e5: mov 0x230(%rax),%rax Setting skb->dev before the call in tap.c fixes the issue. BUG: kernel NULL pointer dereference, address: 0000000000000230 RIP: 0010:virtio_net_hdr_to_skb.constprop.0+0x335/0x410 [tap] Code: 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 RSP: 0018:ffffc90005c27c38 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888298f25300 RCX: 0000000000000010 RDX: 0000000000000005 RSI: ffffc90005c27cb6 RDI: ffff888298f25300 RBP: ffffc90005c27c80 R08: 00000000ffffffea R09: 00000000000007e8 R10: ffff88858ec77458 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000014 R14: ffffc90005c27e08 R15: ffffc90005c27cb6 FS: 0000000000000000(0000) GS:ffff88858ec40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000230 CR3: 0000000281408006 CR4: 00000000003706e0 Call Trace: tap_get_user+0x3f1/0x540 [tap] tap_sendmsg+0x56/0x362 [tap] ? get_tx_bufs+0xc2/0x1e0 [vhost_net] handle_tx_copy+0x114/0x670 [vhost_net] handle_tx+0xb0/0xe0 [vhost_net] handle_tx_kick+0x15/0x20 [vhost_net] vhost_worker+0x7b/0xc0 [vhost] ? vhost_vring_call_reset+0x40/0x40 [vhost] kthread+0xfa/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30

Published: 2025-06-18 Last update: 2026-06-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-50073 is rated Low Risk (29.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.07%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-50073

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-14 0.02% 0.07% +0.06%
2 2025-06-18 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-50073

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2022-50073

GitHub Security Advisory for CVE-2022-50073

GHSA-j9xf-8j9q-6cvr · Severity: medium — In the Linux kernel, the following vulnerability has been resolved: net: tap: NULL pointer...

OS Trackers for CVE-2022-50073

vendor priority summary link
debian not yet assigned CVE-2022-50073 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2022-50073
redhat medium — https://access.redhat.com/security/cve/CVE-2022-50073
suse medium — https://www.suse.com/security/cve/CVE-2022-50073/
ubuntu medium CVE-2022-50073 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 148, not-affected 96, released 92, needed 70. https://ubuntu.com/security/CVE-2022-50073

Affected software / configurations for CVE-2022-50073

Vendor Product Version Raw CPE
linux linux_kernel >= 4.14.226, < 4.15 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.19.181, < 4.20 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.4.106, < 5.5 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.10.24, < 5.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11.7, < 5.12 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.12.1, < 5.19.4 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:-:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc3:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc4:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc5:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc6:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc7:*:*:*:*:*:*
linux linux_kernel 5.12 cpe:2.3:o:linux:linux_kernel:5.12:rc8:*:*:*:*:*:*

References for CVE-2022-50073

cvelogic Threat Intelligence