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TI-2026-52467 Aliases CVE-2026-74684GHSA-23q4-679m-qgxw

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

Priority LOW 30Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

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().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00146 3rd percentileScored 2026-11-07
Fix Partial Linux (Linux): 4.15, 4.20, 5.5 +8Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.14.226 to before 4.15; 4.19.181 to before 4.20; 5.4.106 to before 5.5; 5.10.24 to before 5.11; 5.11.7 to before 5.124.15, 4.20, 5.5, 5.11, 5.12Patch availableCNA
LinuxLinux5.12 and later6.1.191, 6.6.160, 6.12.105, 6.18.45, 7.1.9, 7.2Patch availableCNA
  • Linux VendorLinux Affected 4.14.226 to before 4.15; 4.19.181 to before 4.20; 5.4.106 to before 5.5; 5.10.24 to before 5.11; 5.11.7 to before 5.12 Fixed in 4.15, 4.20, 5.5, 5.11, 5.12 Patch available CNA
  • Linux VendorLinux Affected 5.12 and later Fixed in 6.1.191, 6.6.160, 6.12.105, 6.18.45, 7.1.9, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 4.15, 4.20, 5.5, 5.11, 5.12
  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.105, 6.18.45, 7.1.9, 7.2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-74684
  2. 2026-10-03 Alias added: GHSA-23q4-679m-qgxw
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@61dd022c55c7307ec119e5672cb141cccbecf3b1 · CNA
  5. 2026-10-21 1 new reference · CNA
  6. 2026-10-30 CVSS score changed · Red Hat
  7. 2026-10-30 Fix available: Linux/Linux@1d022885f3e6e0e238815391a4afaf3a4fb0a442, Linux/[email protected] · CNA
  8. 2026-10-30 1 new reference · CNA

References

Other 6

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences