TI-2026-79859 Aliases CVE-2026-99066 GHSA-4qj9-2gm5-pxqj

Linux kernel CAN skb headers can trigger kernel panic

LOW 22Published 2026-10-23 · Updated 2026-10-23

Key facts

Attack vector: —
Privileges required: —
User interaction: —
Attack complexity: —
Impact type: —
Confidentiality · integrity · availability: —
Fix status: Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The Linux kernel from 7.0 is affected. The CAN device code stopped resetting the MAC, network and transport header offsets in init_can_skb(), so receive skbs keep an invalid MAC header value. When such an skb reaches packet_rcv_spkt() on a SOCK_PACKET socket, a length calculation overflows and the kernel panics, halting the whole machine. The same flaw was reported and fixed in 2014, but packet_rcv_spkt() was never hardened.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: can: dev: init_can_skb(): restore skb header initialization Commit 9f10374bb024 ("can: remove private CAN skb headroom infrastructure") removed the skb_reset_mac_header()/skb_reset_network_header()/ skb_reset_transport_header() calls from init_can_skb(). As a result, RX skbs from alloc_can_skb() and friends again carry mac_header = 0xFFFF. When such an skb reaches packet_rcv_spkt() (SOCK_PACKET), the push length calculation overflows and triggers skb_under_panic -> kernel BUG -> full machine panic. The same issue was originally reported in 2014 on linux-can and fixed by commit 969439016d2c ("can: add missing initialisations in CAN related skbuffs"). packet_rcv_spkt() itself has never been hardened: only packet_rcv() and tpacket_rcv() gained dev_has_header() checks in commit d549699048b4 ("net/packet: fix packet receive on L3 devices without visible hard header").

Why it matters now

EPSS 0.00156 4th percentileScored 2026-11-07

Fix Fixed Linux (Linux): 7.2.11, 7.3

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Linux	Linux	7.0 and later	7.2.11, 7.3	Patch available	CNA

Linux VendorLinux Affected 7.0 and later Fixed in 7.2.11, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

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

CPE	Versions	Role	Vendor
cpe:2.3:o:linux:linux_kernel::::::::	—	—	Linux

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

Remediation

The Linux kernel fixes this in versions 7.2.11 and 7.3.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Fix · CNA Linux (Linux) Fixed in 7.2.11, 7.3

Vendor assessments

Red Hat

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

Not affected: 7 products

Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9
Red Hat OpenShift Container Platform 4
Red Hat OpenShift Container Platform 5

Timeline

2026-10-23 Threatist record created from CVE-2026-99066
2026-10-23 Alias added: GHSA-4qj9-2gm5-pxqj
2026-10-27 Affected versions changed · Red Hat
2026-10-27 CVSS score added · Red Hat
2026-10-29 Affected versions changed · Red Hat
2026-11-06 Affected versions changed · Red Hat

References

Other 2

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