CVE-2026-98237

Summary

In the Linux kernel, the following vulnerability has been resolved:

net: wwan: mhi_wwan_mbim: guard against a cyclic NDP chain

The NDP traversal in mhi_mbim_rx() only stops when wNextNdpIndex is zero. Nothing requires the offsets to advance, so a modem that points an NDP at itself, or at an earlier NDP, keeps the loop spinning forever on one CPU.

Break out when the next NDP offset is not larger than the current one.

Verified in a QEMU guest with a fault injector feeding the driver's receive callback an NTB whose single NDP points at itself: the unpatched driver spins in mhi_mbim_rx() with one CPU pinned at 100% and the thread never returns. With this check the loop terminates within one iteration.

Changes in v2: move the non-increasing check to the wNextNdpIndex retrieval site, as suggested by Loic Poulain, instead of tracking the previous offset in a separate variable.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 3ed36ee1b29b028f6bc2ebe100152f61a33df05aaffected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < e4b2c7b50d4f4aa1ddfff731b136d65f65b2b526affected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 19b5e8dd884a530d04482e1a8e547f43cad17ed7affected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 24ade82d6d993274e99c2c6998848751c35292e7affected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 8dad70ff7e25cbcfbcb5101fdbf36d98003eb653affected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 829fec45122da58d77a55a3b7ca514dafab98e77affected
LinuxLinuxaa730a9905b7b079ef2fffdab7f15dbb842f5c7c < 5d063822ac5184939c1ed377a339a01d8ae814e8affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux5.15.222 <= 5.15.*unaffected
LinuxLinux6.1.189 <= 6.1.*unaffected
LinuxLinux6.6.158 <= 6.6.*unaffected
LinuxLinux6.12.112 <= 6.12.*unaffected
LinuxLinux6.18.54 <= 6.18.*unaffected
LinuxLinux7.2.8 <= 7.2.*unaffected
LinuxLinux7.3-rc4 <= *unaffected

Weaknesses

References