CVE-2026-72451

xfrm: Fix xfrm state cache insertion race

Published Aug 15, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

xfrm: Fix xfrm state cache insertion race

The xfrm input state cache insertion code checks the validity of
the state before acquiring the global xfrm_state_lock. Thus it's
possible for someone else to kill the state after it passed the
validity check, and then the insertion will add the dead state
to the cache.

Fix this by moving the validity check inside the lock.

This entire function is called on the input path, where BH must
be off (e.g., the caller of this function xfrm_input acquires
its spinlocks without disabling BH).

So there is no need to disable BH here or take the RCU read lock.
Remove both and replace them with an assertion that trips if BH
is accidentally enabled on some future calling path.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8781-1 Linux kernel (NVIDIA Tegra) vulnerabilities
Ubuntu USN Ubuntu USN USN-8816-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8816-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8816-3 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-8816-4 Linux kernel (GKE) vulnerabilities
Ubuntu USN Ubuntu USN USN-8888-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8888-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8917-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8918-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-9003-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-9024-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9025-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-9026-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-9040-1 Linux kernel (Low Latency NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-9043-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-9066-1 Linux kernel (HWE) vulnerabilities
History
Type Values Removed Values Added
Weaknesses CWE-362
Type Values Removed Values Added
Weaknesses CWE-362
Type Values Removed Values Added
Weaknesses CWE-362
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
Weaknesses CWE-362
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: xfrm: Fix xfrm state cache insertion race The xfrm input state cache insertion code checks the validity of the state before acquiring the global xfrm_state_lock. Thus it's possible for someone else to kill the state after it passed the validity check, and then the insertion will add the dead state to the cache. Fix this by moving the validity check inside the lock. This entire function is called on the input path, where BH must be off (e.g., the caller of this function xfrm_input acquires its spinlocks without disabling BH). So there is no need to disable BH here or take the RCU read lock. Remove both and replace them with an assertion that trips if BH is accidentally enabled on some future calling path.
Title xfrm: Fix xfrm state cache insertion race
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Aug 17, 2026, 5:44 AM
Reserved
Aug 9, 2026, 3:40 AM
Status
Received
Published
Aug 15, 2026, 6:22 AM
Modified
Aug 17, 2026, 6:19 AM
Severity
Moderate
Public date
Aug 15, 2026, 12:00 AM