What is CVE-2026-63911?

CVE-2026-63911 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 6.14 onward and patched in 6.18.35, 7.0.12 and 7.1. CVE-2026-63911 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-63911?

CVE-2026-63911 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-63911?

Yes, CVE-2026-63911 has been patched. Fixed versions include 6.18.35, 7.0.12 and 7.1. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-63911 actively exploited?

CVE-2026-63911 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-63911

High

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.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-07-27

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 6.14 and later are affected. Fixed in 6.18.35, 7.0.12, 7.1 and their respective stable series.

Affected from

≥ 6.14

Fixed in

✓ 6.18.35 6.18.x ✓ 7.0.12 7.0.x ✓ 7.1

References

3 total

Details

CVE ID CVE-2026-63911

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-07-19

Modified 2026-07-27

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-63911?

CVE-2026-63911 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 6.14 onward and has been patched in 6.18.35, 7.0.12 and 7.1. CVE-2026-63911 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-63911?

CVE-2026-63911 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-63911?

Yes. CVE-2026-63911 has been patched. Fixed versions include 6.18.35, 7.0.12 and 7.1. If you are running Linux kernel 6.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-63911 actively exploited?

No. CVE-2026-63911 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.