Vulnerability · CVE-2026-74667
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 t…
Published Aug 22, 2026 · catalog updated Oct 14, 2026 · the affected product
Check if you run it
No confirmed exploitation is on record for CVE-2026-74667. EPSS is 0.14%. Act only if a listed version of the affected product is installed.
Gaps on this record
- No plain product name is stored. The page cannot tell you which product to check.
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.14%
- Remediation
- Not established
- Affected products
- See sources for product scope
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.
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix CVE-2026-74667
Recommended remediation
No required-action text, fix commit, or clear fixed-version range is stored yet.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-74667. EPSS is 0.14%. Act only if a listed version of the affected product is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.14%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Aug 22, 2026 · NIST NVD
Detected
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 __d
Oct 14, 2026 · NIST NVD
Updated
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 __d
Sources
- CVE.orgVulnerability recordCVE-2026-74667
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-74667
30-day exploitation probability 0.1%
first.org - NIST NVDVulnerability recordCVE-2026-74667
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,
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.