CVE-2026-74701
net/openvswitch: check Ethernet header length in key_extract()
Description
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.
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
Solution
- Apply the kernel patch that checks header length in key_extract.
- Update the Linux kernel to a fixed version.
- Validate packet header lengths before processing.
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-2026-74701.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74701 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-2026-74701
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-2026-74701 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74701 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.
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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': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': 'e85278afd4890dd190ba3c7a1b1a712b801c9fe1', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': '81f9b09f0ea3ba9ab966dd17e9f32625a14555e9', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': '831471718f6e19aed1a330b03b53190a90e06466', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': 'd8bea341b183190ce6c055ab0e64ab78eb9a7290', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': '0b60b55652ba772b173dddc63f3851e1d2dd5927', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': 'a8139285c8925efe59af28a9169bb2fda91bff15', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': '9b8cfbb58b85bfa7a78fac47fdc77396cd01f699', 'versionType': 'git'}, {'status': 'affected', 'version': '217ac77a3c2524d999730b2a80b61fcc2d0f734a', 'lessThan': 'cf6f8b29befb92173659bcef6a441d274947bfae', 'versionType': 'git'}], 'programFiles': ['net/openvswitch/flow.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.10'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.10', '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/openvswitch/flow.c'], 'defaultStatus': 'affected'}] Added Description 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. Added Reference https://git.kernel.org/stable/c/0b60b55652ba772b173dddc63f3851e1d2dd5927 Added Reference https://git.kernel.org/stable/c/81f9b09f0ea3ba9ab966dd17e9f32625a14555e9 Added Reference https://git.kernel.org/stable/c/831471718f6e19aed1a330b03b53190a90e06466 Added Reference https://git.kernel.org/stable/c/9b8cfbb58b85bfa7a78fac47fdc77396cd01f699 Added Reference https://git.kernel.org/stable/c/a8139285c8925efe59af28a9169bb2fda91bff15 Added Reference https://git.kernel.org/stable/c/cf6f8b29befb92173659bcef6a441d274947bfae Added Reference https://git.kernel.org/stable/c/d8bea341b183190ce6c055ab0e64ab78eb9a7290 Added Reference https://git.kernel.org/stable/c/e85278afd4890dd190ba3c7a1b1a712b801c9fe1