Linux Kernel up to 7.3-rc3 mhi_wwan_mbim mhi_mbim_rx uninitialized variable

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.3-rc3. It has been declared as very critical. Impacted is the function mhi_mbim_rx of the component mhi_wwan_mbim. The manipulation results in uninitialized variable. This vulnerability is known as CVE-2026-98236. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 7.3-rc3. Affected is the function mhi_mbim_rx of the component mhi_wwan_mbim. The manipulation with an unknown input leads to a uninitialized variable vulnerability. CWE is classifying the issue as CWE-457. The code uses a variable that has not been initialized, leading to unpredictable or unintended results. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: wwan: mhi_wwan_mbim: check skb_copy_bits() return value mhi_mbim_rx() ignores the return value of skb_copy_bits() when it copies each datagram out of the NTB. The datagram offset and length come from the DPE, which is only checked to lie within the NTB itself, so a modem can point a datagram outside the received skb. The copy then fails and the freshly allocated skbn is passed to netif_rx() with its uninitialized contents still in place, leaking kernel heap memory into the network stack. Free the skb and account an error when the copy fails. Verified in a QEMU guest with a fault injector pointing a DPE outside the received NTB: the copy fails, and the unpatched driver hands the uninitialized skbn to the network stack (observed as "unknown protocol" on bytes that were never written). With this check the failed datagram is dropped and counted as an rx error. Changes in v2: factor the free-and-count sequence out into mhi_mbim_rx_drop(), shared with the unknown-protocol path, as suggested by Loic Poulain.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-98236 since 09/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 10/06/2026).

Upgrading to version 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8 or 7.3-rc4 eliminates this vulnerability. Applying the patch 650af68435eaee783824457d2ef78cc5c03c1e88/350fd3125ee26b5243935fd9e2b4d162ffba430a/dd136f1fdd1059f3bc25ede3a8def8f0ee151ce7/298659c3677bf622afa9d77549cb4a967f9541e9/7e98216e9da08b79e07a514d2a4f7646f8c9ccb9/31550d585589fde1ae95bf7f7a8188b2d2fdf1c7 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

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

Exploitinginfo

Class: Uninitialized variable
CWE: CWE-457 / CWE-453
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 5.15.222/6.1.189/6.6.158/6.12.112/6.18.54/7.2.8/7.3-rc4
Patch: 650af68435eaee783824457d2ef78cc5c03c1e88/350fd3125ee26b5243935fd9e2b4d162ffba430a/dd136f1fdd1059f3bc25ede3a8def8f0ee151ce7/298659c3677bf622afa9d77549cb4a967f9541e9/7e98216e9da08b79e07a514d2a4f7646f8c9ccb9/31550d585589fde1ae95bf7f7a8188b2d2fdf1c7

Timelineinfo

09/25/2026 CVE reserved
10/06/2026 +11 days Advisory disclosed
10/06/2026 +0 days VulDB entry created
10/06/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98236 (🔒)
GCVE (CVE): GCVE-0-2026-98236
GCVE (VulDB): GCVE-100-414210

Entryinfo

Created: 10/06/2026 13:42
Changes: 10/06/2026 13:42 (59)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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