Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-74684— net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

在 Linux 内核中，以下漏洞已修复： 网络子系统：tap 模块：在 tap_get_user_xdp() 中解析 virtio 网络头之前设置 skb->dev 提交 4f61f133f354（“net: tap: 当 skb->dev 为空时，dev_parse_header_protocol 中出现空指针解引用”）通过在调用 tun_vnet_hdr_to_skb() 之前赋值 skb->dev，修复了 tap_get_user() 中的一个崩溃问题。这是必要的，因为 virtio_net_hdr_to_s

CVSS 7.1 · High EPSS 0.14% · P4

Possible ATT&CK Techniques 1 AI

T1068 · Exploitation for Privilege Escalation

Affected Version Matrix 20

VendorProduct Version RangeStatus
Linux Linux 924a9bc362a5223cd448ca08c3dde21235adc310< 15583b07fd691a844fbf7b3ad612cdc9e9a657c0 affected
924a9bc362a5223cd448ca08c3dde21235adc310< 8b444b126cd8e4473e652f529753ed4dd1360a9c affected
924a9bc362a5223cd448ca08c3dde21235adc310< 164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b affected
924a9bc362a5223cd448ca08c3dde21235adc310< 3874892dd27d5387aa9a06f58d9060f18f351d24 affected
ea3fb2ce5fa794d02135f5c079e05cd6fc3f545d affected
54ef8243c3c8e90f1ea5792e6752e021a25c8eb3 affected
ca278267d6cd9544645731732455b6b20cb0e895 affected
faa3baa2828c5e1c4374f3e60041f75c64f5fcb6 affected
… +12 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-74684

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp() The commit 4f61f133f354 ("net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null") fixed a crash in tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb(). This is required because virtio_net_hdr_to_skb() may invoke dev_parse_header_protocol(), which dereferences skb->dev. Without the assignment, a NULL pointer dereference can occur. However, tap_get_user_xdp() still parses the virtio-net header before assigning skb->dev. When the vhost TX path passes an XDP buffer containing a GSO virtio-net header but the protocol is set to zero on purpose, tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev is still NULL, resulting in a crash. Fix this by looking up the tap device and assigning skb->dev before calling tun_vnet_hdr_to_skb(), matching the ordering already used in tap_get_user(). Preserve the existing RCU read-side critical section across dev_queue_xmit().
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 924a9bc362a5223cd448ca08c3dde21235adc310 ~ 15583b07fd691a844fbf7b3ad612cdc9e9a657c0 -
Linux Linux 5.12 -

II. Public POCs for CVE-2026-74684

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-74684

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-74684 (4)

Same Patch Batch · Linux · 2026-08-22 · 150 CVEs total

CVE-2026-74705 10.0 CRITICAL udp: fix potential use-after-free in tunnel segmentation
CVE-2026-74612 10.0 CRITICAL veth: fix skb length accounting after XDP frag adjustment
CVE-2026-74616 9.8 CRITICAL xdp: reject clones that overrun skb_shared_info tailroom
CVE-2026-74591 9.8 CRITICAL mm/filemap: __filemap_add_folio() restore index before retrying
CVE-2026-74688 9.8 CRITICAL sctp: clear control chunk transport if it is being removed
CVE-2026-74597 9.8 CRITICAL ip6_tunnel: clear skb2->cb[] in ip6ip6_err()
CVE-2026-74617 9.8 CRITICAL dibs: initialise dibs->lock in dibs_dev_alloc()
CVE-2026-74628 9.8 CRITICAL net/x25: fix use-after-free of the socket by its timers
CVE-2026-74608 9.8 CRITICAL smb: client: Fix use-after-free in cifs_try_adding_channels()
CVE-2026-74669 9.8 CRITICAL ipvs: clear IPv4 options after rebasing tunnel ICMP errors
CVE-2026-74587 9.8 CRITICAL sctp: fix use-after-free of cached ASCONF chunk
CVE-2026-74662 9.8 CRITICAL inet: frags: publish queues before arming timer
CVE-2026-74723 9.8 CRITICAL btrfs: lzo: reject inline extents without valid headers
CVE-2026-74730 9.8 CRITICAL NFS: Pin the 'struct nfs_server' during a FREE_STATEID call
CVE-2026-74727 9.8 CRITICAL ovpn: skip rehash for peers already removed from by_id
CVE-2026-74586 9.8 CRITICAL sctp: clear new_transport when removing a peer
CVE-2026-74611 9.8 CRITICAL tls: rx: restore msg_iter before TLS 1.3 optimistic retry
CVE-2026-74588 9.8 CRITICAL sctp: keep chunk->transport in step with the list it is queued on
CVE-2026-74712 9.3 CRITICAL vdpa/mlx5: Fix buffer length in create_direct_keys()
CVE-2026-74665 9.1 CRITICAL net: fix skb length accounting after generic XDP frag adjustment

Showing top 20 of 150 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-74684

No comments yet

Leave a comment