Linux Kernel up to 7.2.5 Bluetooth read_supported_features evt_prefix_len 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.
6.0	$0-$5k	0.00+

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 7.2.5. Affected by this issue is the function read_supported_features of the component Bluetooth. Executing a manipulation of the argument evt_prefix_len can lead to out-of-bounds. This vulnerability is tracked as CVE-2026-90251. The attack can be launched remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 7.2.5. This vulnerability affects the function read_supported_features of the component Bluetooth. The manipulation of the argument evt_prefix_len 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: Bluetooth: MSFT: validate evt_prefix_len against the response length read_supported_features() only checks that the response covers the fixed part of struct msft_rp_read_supported_features, which is 11 bytes: if (skb->len < sizeof(*rp)) { bt_dev_err(hdev, "MSFT supported features length mismatch"); goto failed; } evt_prefix[] is a flexible array member and rp->evt_prefix_len is an unvalidated u8 taken straight out of that response, so msft->evt_prefix = kmemdup(rp->evt_prefix, rp->evt_prefix_len, GFP_KERNEL); copies up to 255 bytes from a reply that may have carried none of them. What is copied is data the controller never sent, and it is then used to match incoming vendor events in msft_vendor_evt(). This is not an out-of-bounds access. An skb data allocation always has at least SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) bytes past the payload, which is more than the 255 byte maximum, so the read stays inside the allocation and KASAN does not report it. It is still a read of bytes the host was never given, with the length fully controlled by the controller. Reject a response that is too short for the prefix it declares. Verified with an emulated controller over /dev/vhci on a KASAN kernel, with vhci made to advertise an MSFT opcode the way btintel, btqca, btmtk and btrtl do unconditionally. A reply of exactly 11 bytes declaring evt_prefix_len = 255 reaches kmemdup and copies 255 bytes ("skb->len=11 evt_prefix_len=255", with the copied buffer dumped); since the reply ends at the fixed part, all 255 come from past the end of the response. No KASAN report is produced, as expected from the allocation slack described above. With this patch the response is rejected with "MSFT event prefix length mismatch" and msft->evt_prefix is left unset.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-90251 since 09/11/2026. The exploitation appears to be easy. The attack can be initiated remotely. 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 09/17/2026).

Upgrading to version 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch dce783a10e70f013410f5b583a29fc3286899629/21f539c59ed330b671d75fd119c5f659ff92fbd1/52b1b3b4d403cbda1b70ce2385e1a71f166a87ba/e804d54a5a99d99250490e68093eff7190472e6f/620c2631cff490d14d0b9d56f185cc745806d6d7/7c2658023d839b651368a5b8b781bf9a817647cb/63562cfaea8a650fdb31ee8de21c32e3600be642/0079e1a944634ab2dc1c7cdec1144486d096407e is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.269
• 5.15.220
• 6.1.187
• 6.6.156
• 6.12.109
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 6.18.30
• 6.18.31
• 6.18.32
• 6.18.33
• 6.18.34
• 6.18.35
• 6.18.36
• 6.18.37
• 6.18.38
• 6.18.39
• 6.18.40
• 6.18.41
• 6.18.42
• 6.18.43
• 6.18.44
• 6.18.45
• 6.18.46
• 6.18.47
• 6.18.48
• 6.18.49
• 6.18.50
• 6.18.51
• 7.2.0
• 7.2.1
• 7.2.2
• 7.2.3
• 7.2.4
• 7.2.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.270/5.15.221/6.1.188/6.6.157/6.12.110/6.18.52/7.2.6/7.3-rc1
Patch: dce783a10e70f013410f5b583a29fc3286899629/21f539c59ed330b671d75fd119c5f659ff92fbd1/52b1b3b4d403cbda1b70ce2385e1a71f166a87ba/e804d54a5a99d99250490e68093eff7190472e6f/620c2631cff490d14d0b9d56f185cc745806d6d7/7c2658023d839b651368a5b8b781bf9a817647cb/63562cfaea8a650fdb31ee8de21c32e3600be642/0079e1a944634ab2dc1c7cdec1144486d096407e

Timelineinfo

09/11/2026 CVE reserved
09/17/2026 +6 days Advisory disclosed
09/17/2026 +0 days VulDB entry created
09/17/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-90251 (🔒)
GCVE (CVE): GCVE-0-2026-90251
GCVE (VulDB): GCVE-100-406792

Entryinfo

Created: 09/17/2026 21:12
Changes: 09/17/2026 21:12 (60)
Complete: 🔍
Cache ID: 216::103

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