CVE-2026-98236

/// Technical description

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

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References