Linux Kernel up to 7.1.8 Open vSwitch net/openvswitch/flow.c key_extract protocol out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k0.00

Summaryinfo

A vulnerability classified as very critical was found in Linux Kernel up to 7.1.8. Affected is the function key_extract of the file net/openvswitch/flow.c of the component Open vSwitch. Executing a manipulation of the argument protocol can lead to out-of-bounds. This vulnerability is tracked as CVE-2026-74701. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 7.1.8 and classified as very critical. This vulnerability affects the function key_extract of the file net/openvswitch/flow.c of the component Open vSwitch. The manipulation of the argument protocol with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-74701 since 08/15/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/22/2026).

Upgrading to version 5.10.265, 5.15.216, 6.1.183, 6.6.152, 6.12.104, 6.18.45 or 7.1.9 eliminates this vulnerability. Applying the patch e85278afd4890dd190ba3c7a1b1a712b801c9fe1/81f9b09f0ea3ba9ab966dd17e9f32625a14555e9/831471718f6e19aed1a330b03b53190a90e06466/d8bea341b183190ce6c055ab0e64ab78eb9a7290/0b60b55652ba772b173dddc63f3851e1d2dd5927/a8139285c8925efe59af28a9169bb2fda91bff15/9b8cfbb58b85bfa7a78fac47fdc77396cd01f699/cf6f8b29befb92173659bcef6a441d274947bfae is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.265/5.15.216/6.1.183/6.6.152/6.12.104/6.18.45/7.1.9
Patch: e85278afd4890dd190ba3c7a1b1a712b801c9fe1/81f9b09f0ea3ba9ab966dd17e9f32625a14555e9/831471718f6e19aed1a330b03b53190a90e06466/d8bea341b183190ce6c055ab0e64ab78eb9a7290/0b60b55652ba772b173dddc63f3851e1d2dd5927/a8139285c8925efe59af28a9169bb2fda91bff15/9b8cfbb58b85bfa7a78fac47fdc77396cd01f699/cf6f8b29befb92173659bcef6a441d274947bfae

Timelineinfo

08/15/2026 CVE reserved
08/22/2026 +7 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
08/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74701 (🔒)
GCVE (CVE): GCVE-0-2026-74701
GCVE (VulDB): GCVE-100-394492

Entryinfo

Created: 08/22/2026 19:04
Changes: 08/22/2026 19:04 (61)
Complete: 🔍
Cache ID: 216::103

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