CVE-2023-53354: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53354 affects the Linux kernel's skbuff subsystem. The vulnerability was discovered in September 2025 and involves a bug in the skb_segment() function where calling zero copy functions before using skbuff frags could lead to kernel panic (NVD).

The vulnerability was introduced by commit bf5c25d60861 which added zero copy function calls in skb_segment(). The bug occurs because skb_orphan_frags() may change the number of fragments or allocate new fragments, leaving nrfrags and frag pointing to old values. This results in the code prematurely hitting i >= nrfrags and attempting to move to the next frag_skb using a NULL list_skb pointer, causing a kernel panic (NVD).

When exploited, this vulnerability can cause a kernel NULL pointer dereference at address 0x00000000000000bc, leading to a system crash. The issue affects the networking stack's packet segmentation functionality (NVD).

The vulnerability requires local access to trigger the bug through network packet handling operations. A detailed stack trace shows the vulnerability can be triggered through various networking paths including TCP GSO segmentation, network queueing disciplines, and virtual networking interfaces (NVD).

The fix involves moving the call to zero copy functions before using frags and nr_frags values. The vulnerability has been patched in multiple Linux distributions including Red Hat Enterprise Linux (Red Hat).