CVE Catalog

CVE-2026-74701

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel, the openvswitch module's key_extract() function does not check the Ethernet header length before accessing it, which can lead to a kernel BUG in __skb_pull() for packets arriving on ARPHRD_NONE devices such as TUN. The fix is to call check_header() before accessing the Ethernet header.

Risk Assessment

An attacker can cause a kernel crash (kernel BUG) by sending a specially crafted packet, leading to denial of service (DoS).

Recommendation

Apply the Linux kernel patch that adds a check_header() call in key_extract(), or update the kernel to a version containing this fix.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: net/openvswitch: check Ethernet header length in key_extract() When a packet arrives on an ARPHRD_NONE device (e.g. TUN), ovs_flow_key_extract() trusts the user-provided skb->protocol field: if it is ETH_P_TEB, the packet is classified as MAC_PROTO_ETHERNET and key_extract() is called without ensuring the skb has ETH_HLEN (14) bytes of linear data. key_extract() unconditionally pulls 2 * ETH_ALEN bytes for MAC addresses and parse_ethertype() pulls 2 more, either of which triggers a kernel BUG in __skb_pull() when the linear area is too small. kernel BUG at include/linux/skbuff.h:2848! RIP: 0010:key_extract+0xa7e/0xd90 net/openvswitch/flow.c:933 ovs_flow_key_extract+0x419/0xa70 ovs_vport_receive+0x222/0x390 netdev_frame_hook+0x3e0/0x630 tun_get_user+0x2d0c/0x38e0 Fixed by calling check_header() in key_extract() before accessing the Ethernet header.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS