CVE-2026-53235

Technical Description

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

net: add pskb_may_pull() to skb_gro_receive_list()

skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without

first ensuring the data is in the linear area via pskb_may_pull(). When

the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in

page fragments) while skb_gro_offset is non-zero (after IP+TCP header

parsing). The skb_pull() then decrements skb->len by skb_gro_offset

but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len)

in __skb_pull().

The UDP fraglist GRO path already contains this guard at

udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides

centralized protection for all callers (TCP, UDP, and any future

protocols), and ensures the precondition of skb_pull() is satisfied

before it is called.

On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the

skb is not held as a new GRO head and is instead delivered through the

normal rec

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. 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.

Affected Products

References