SEPTEMBER 8, 2026
Live Feed
Back to database
Case File

CVE-2026-63911

HIGH · CVSS 7.8 EPSS 0.16%

Source: NVD + CISA KEV + EPSS · Published 2026-07-19 · Last synced 2026-08-18

CyberRota Analysis

AI-Generated

The vulnerability affects the Linux kernel's IPTFS implementation, where the cloning of Security Associations (SAs) can lead to use-after-free and double-free conditions due to improper handling of runtime state. This flaw allows an attacker to exploit queued packets, potentially leading to system instability or unauthorized access. Organizations using affected Linux distributions should prioritize patching this vulnerability to mitigate the risk of exploitation.

CVE
CVE-2026-63911
Severity
HIGH
CVSS
7.8
EPSS
0.16%
Linux

Original NVD Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: reset runtime state when cloning SAs iptfs_clone_state() clones the IPTFS mode data with kmemdup(). This copies runtime objects which must not be shared with the original SA, including the embedded sk_buff_head, hrtimers, spinlock, and in-flight reassembly/reorder state. If xfrm_state_migrate() fails after clone_state() but before the later init_state() call has reinitialized those fields, the cloned state can be destroyed by xfrm_state_gc_task() with list and timer state copied from the original SA. With queued packets this lets the clone splice and free skbs owned by the original IPTFS queue, leading to use-after-free and double-free reports in iptfs_destroy_state() and skb release paths. Reinitialize the clone's runtime state before publishing it through x->mode_data. Because clone_state() now publishes a destroyable mode_data object before init_state(), take the mode callback module reference there. Avoid taking it again from __iptfs_init_state() for the same object.