CVE-2026-23172 net: wwan: t7xx: fix potential skb->frags overflow in RX path
A buffer overflow in the Linux kernel t7xx WWAN driver allows malicious firmware to corrupt memory, causing crashes or potential code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23172?
CVE-2026-23172 is a high-severity memory corruption vulnerability in Linux kernel, published on 14 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net: wwan: t7xx: fix potential skb->frags overflow in RX path
When receiving data in the DPMAIF RX path, the t7xx_dpmaif_set_frag_to_skb() function adds page fragments to an skb without checking if the number of fragments has exceeded MAX_SKB_FRAGS. This could lead to a buffer overflow in skb_shinfo(skb)->frags[] array, corrupting adjacent memory and potentially causing kernel crashes or other undefined behavior.
This issue was identified through static code analysis by comparing with a similar vulnerability fixed in the mt76 driver commit b102f0c522cf ("mt76: fix array overflow on receiving too many fragments for a packet").
The vulnerability could be triggered if the modem firmware sends packets with excessive fragments. While under normal protocol conditions (MTU 3080 bytes, BAT buffer 3584 bytes), a single packet should not require additional fragments, the kernel should not blindly trust firmware behavior. Malicious, buggy, or compromised firmware could potentially craft packets with more fragments than the kernel expects.
Fix this by adding a bounds check before calling skb_add_rx_frag() to ensure nr_frags does not exceed MAX_SKB_FRAGS.
The check must be performed before unmapping to avoid a page leak and double DMA unmap during device teardown.
Which versions are affected by CVE-2026-23172?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-23172?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-23172 being exploited?
There is no known exploitation of CVE-2026-23172 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-23172, DEBIAN-CVE-2026-23172, GHSA-m5mw-gf4c-pwc3, ROOT-OS-UBUNTU-2404-CVE-2026-23172, UBUNTU-CVE-2026-23172.