CVE-2026-72340

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: microchip: vcap: fix races on the shared Super VCAP block

The VCAP instances on a chip are not independent, yet they are locked

independently. On sparx5 and lan969x the IS0 and IS2 instances are

backed by the same Super VCAP hardware block and share its cache and

command registers: every access drives the shared VCAP_SUPER_CTRL

register and moves data through the shared cache registers.

Accessing one instance therefore races with accessing another. The

per-instance admin->lock cannot prevent this, as each instance takes a

different lock.

The locking issue is mostly disguised by the fact that the core usage of

the vcap api runs under rtnl. However, the full rule dump in debugfs

decodes rules straight from hardware (a READ command followed by a cache

read) and runs outside rtnl, so it races a concurrent tc-flower rule

write to another Super VCAP instance.

Besides corrupting the dump, the read repopulates the sh

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References