CVE-2026-43495

Description

In the Linux kernel, the following vulnerability has been resolved: net: wwan: t7xx: validate port_count against message length in t7xx_port_enum_msg_handler t7xx_port_enum_msg_handler() uses the modem-supplied port_count field as a loop bound over port_msg->data[] without checking that the message buffer contains sufficient data. A modem sending port_count=65535 in a 12-byte buffer triggers a slab-out-of-bounds read of up to 262140 bytes. Add a sizeof(*port_msg) check before accessing the port message header fields to guard against undersized messages. Add a struct_size() check after extracting port_count and before the loop. In t7xx_parse_host_rt_data(), guard the rt_feature header read with a remaining-buffer check before accessing data_len, validate feat_data_len against the actual remaining buffer to prevent OOB reads and signed integer overflow on offset. Pass msg_len from both call sites: skb->len at the DPMAIF path after skb_pull(), and the validated feat_data_len at the handshake path.

Predictions

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

References

• https://git.kernel.org/stable/c/0e7c074cfcd9bd93765505f9eb8b42f03ed2a744
• https://git.kernel.org/stable/c/2b56d7903ab804481f5233a259d5f341e9fd513c
• https://git.kernel.org/stable/c/9855e063e063158cc5bded576382599dc3133202
• https://git.kernel.org/stable/c/dd4f4c93c1488d7100b9964f2da4c8b3c29652f1
• https://git.kernel.org/stable/c/f94450ce5053b36002995b72d1fa1db3bb08c5bf
• https://www.suse.com/security/cve/CVE-2026-43495.html
• https://security-tracker.debian.org/tracker/CVE-2026-43495
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-43495