CVE-2026-74667
net/packet: reset the MAC header on the packet-socket transmit path
Description
In the Linux kernel, the following vulnerability has been resolved: net/packet: reset the MAC header on the packet-socket transmit path packet_parse_headers() resets the MAC header only for a SOCK_RAW frame whose socket did not bind a protocol. A protocol-bound SOCK_RAW socket, any SOCK_DGRAM frame, and the legacy SOCK_PACKET path therefore leave skb->mac_header unset here. For frames sent via __dev_queue_xmit() this is harmless: it resets the MAC header unconditionally. But the packet-socket PACKET_QDISC_BYPASS path uses dev_direct_xmit(), which does not, so the frame reaches ndo_start_xmit() with the MAC header unset. A driver that reads eth_hdr(skb) on transmit then dereferences skb->head + (u16)~0, an out-of-bounds access ~64 KiB past the head -- the same class fixed for one consumer in commit f5089008f90c ("macsec: do not read an unset MAC header in macsec_encrypt()"). packet_parse_headers() runs only on the transmit path, where skb->data points at the start of the L2 header for every packet-socket type regardless of its length: SOCK_RAW and SOCK_PACKET carry a user-supplied header and SOCK_DGRAM has one built by dev_hard_header(). Reset the MAC header unconditionally, mirroring __dev_queue_xmit(), so the frame is anchored on the bypass path too. Found by 0sec (https://0sec.ai) using automated source analysis; verified against source and matched to the macsec KASAN report in f5089008f90c. Compile-tested.
INFO
Published Date :
Aug. 22, 2026, 4:16 p.m.
Last Modified :
Aug. 22, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74667
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update the Linux kernel to the latest version.
- Apply the relevant security patch for the kernel.
- Recompile the kernel with the fix.
- Verify the fix is applied.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74667.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74667 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74667
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74667 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74667 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 22, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': '1e43a1d66615f411d427f9df1f46dd049d9e3681', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': '4057853a91fb796c4f47c7d1baf1aa085394148e', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': '2610ed4e86a4590234a9d70518c469751c5af231', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': 'b47ba8fe6e1d2df8c92048de5afafd059447dc30', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': '284f3e7a3f1a743fdf89e304fd1f19d5ffcff46d', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': '971aa7d99242bbf09513e27b7a243f0b29ff23ae', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': 'fdd4d7d52358a58e351dd9d82530c04eba8ccd7a', 'versionType': 'git'}, {'status': 'affected', 'version': '75c65772c3d18447d62d3aca5f91b06c16cc25e4', 'lessThan': 'c2707480cfbf19c7619acc9c089d17f20869821f', 'versionType': 'git'}], 'programFiles': ['net/packet/af_packet.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.1'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.1', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.265', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.216', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.183', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.152', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.104', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.45', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.9', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/packet/af_packet.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/packet: reset the MAC header on the packet-socket transmit path packet_parse_headers() resets the MAC header only for a SOCK_RAW frame whose socket did not bind a protocol. A protocol-bound SOCK_RAW socket, any SOCK_DGRAM frame, and the legacy SOCK_PACKET path therefore leave skb->mac_header unset here. For frames sent via __dev_queue_xmit() this is harmless: it resets the MAC header unconditionally. But the packet-socket PACKET_QDISC_BYPASS path uses dev_direct_xmit(), which does not, so the frame reaches ndo_start_xmit() with the MAC header unset. A driver that reads eth_hdr(skb) on transmit then dereferences skb->head + (u16)~0, an out-of-bounds access ~64 KiB past the head -- the same class fixed for one consumer in commit f5089008f90c ("macsec: do not read an unset MAC header in macsec_encrypt()"). packet_parse_headers() runs only on the transmit path, where skb->data points at the start of the L2 header for every packet-socket type regardless of its length: SOCK_RAW and SOCK_PACKET carry a user-supplied header and SOCK_DGRAM has one built by dev_hard_header(). Reset the MAC header unconditionally, mirroring __dev_queue_xmit(), so the frame is anchored on the bypass path too. Found by 0sec (https://0sec.ai) using automated source analysis; verified against source and matched to the macsec KASAN report in f5089008f90c. Compile-tested. Added Reference https://git.kernel.org/stable/c/1e43a1d66615f411d427f9df1f46dd049d9e3681 Added Reference https://git.kernel.org/stable/c/2610ed4e86a4590234a9d70518c469751c5af231 Added Reference https://git.kernel.org/stable/c/284f3e7a3f1a743fdf89e304fd1f19d5ffcff46d Added Reference https://git.kernel.org/stable/c/4057853a91fb796c4f47c7d1baf1aa085394148e Added Reference https://git.kernel.org/stable/c/971aa7d99242bbf09513e27b7a243f0b29ff23ae Added Reference https://git.kernel.org/stable/c/b47ba8fe6e1d2df8c92048de5afafd059447dc30 Added Reference https://git.kernel.org/stable/c/c2707480cfbf19c7619acc9c089d17f20869821f Added Reference https://git.kernel.org/stable/c/fdd4d7d52358a58e351dd9d82530c04eba8ccd7a