CVE-2026-63911

xfrm: iptfs: reset runtime state when cloning SAs

HIGH
7.8
CVSS Score
Published: July 19, 2026 at 02:55 PM UTC
Updated: October 30, 2026 at 02:29 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

6.14 ≤ v < 6.18.356.19 ≤ v < 7.0.120e4fbf013fa566f274ce9b4ce698c75b1f998c526.147.1
Vendor states this is fixed in 7f83d174073234839aea176f265e517e0d50a1d2 (fixed)
Vendor states this is fixed in 9327252e04626d4bb02ca8c0c108fbe8eabf0c5a (fixed)
Vendor states this is fixed in dfb9f6cbfa9826655a49698cf90eb800fce2178e (fixed)
Vendor states this is fixed in 6.14 (unaffected)
Vendor states this is fixed in 6.18.35 (unaffected)
Vendor states this is fixed in 7.0.12 (unaffected)
Vendor states this is fixed in 7.1 (unaffected)

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusANALYZED
CWE
NVD-CWE-noinfo

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