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

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$0-$5k3.08

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.

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.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

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
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

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

Once again VulDB remains the best source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!