CVE Catalog

CVE-2026-98238

Low risk· EPSS 7%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.18%

7th percentile - higher than 7% of all known CVEs

Summary

In the Linux kernel t7xx WWAN driver, t7xx_ccmni_recv_skb() indexes the ccmni_inst[] array without a bounds check. The netif index in the DPMAIF PIT header is five bits wide (0-31) but the array holds only 21 entries, so indexes 21-31 read past it into the callback table, causing the driver to treat arbitrary data as a struct t7xx_ccmni and dereference it.

Risk Assessment

This can cause an out-of-bounds read of kernel memory and dereference of an invalid pointer, leading to a system crash or potential kernel code execution when hostile traffic arrives from the modem.

Recommendation

Update the Linux kernel to a version containing the fix that drops the skb when the netif index is out of range.

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: net: wwan: t7xx: validate the netif index in t7xx_ccmni_recv_skb() The netif index carried in the DPMAIF PIT header is five bits wide, but ccmni_inst[] only has room for NIC_DEV_MAX (21) entries. t7xx_ccmni_recv_skb() indexes the array without a bounds check, so indexes 21 to 31 read past it. The out-of-bounds value lands in the callback table that follows the array, which is never NULL, so the existing !ccmni check does not catch it and the driver dereferences whatever sits there as a struct t7xx_ccmni. Drop the skb when the index is out of range. Verified in a QEMU guest with a fault injector setting the netif index to 25: the unpatched driver reads a value past ccmni_inst[], which lands in the callback table, and dereferences it far enough to queue the skb. With this check the packet is dropped. Well-formed traffic on index 0 is unaffected. Changes in v2: none.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS