What is CVE-2026-64580?

CVE-2026-64580 is a unscored severity Linux kernel vulnerability, affecting Linux kernel versions from 3.0.79 onward and patched in 6.6.148, 6.12.101, 6.18.42 and others. CVE-2026-64580 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64580?

CVE-2026-64580 has a CVSS score of pending NVD analysis out of 10, rated awaiting scoring severity.

Is there a patch available for CVE-2026-64580?

Yes, CVE-2026-64580 has been patched. Fixed versions include 6.6.148, 6.12.101, 6.18.42 and others. If you are running Linux kernel 3.0.79 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-64580 actively exploited?

CVE-2026-64580 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-64580

In the Linux kernel, the following vulnerability has been resolved: xfrm6: clear dst.dev on error to avoid double netdev_put in xfrm6_fill_dst() On the error path where in6_dev_get(dev) returns NULL, xfrm6_fill_dst() releases the device reference with netdev_put() but leaves xdst->u.dst.dev set. dst_destroy() later calls netdev_put(dst->dev) again, so the same net_device reference is released twice, underflowing its refcount (ref_tracker WARNING + "unregister_netdevice: waiting for <dev> to become free"). Clear xdst->u.dst.dev after the netdev_put(), the same way the XFRM device-offload paths xfrm_dev_state_add() and xfrm_dev_policy_add() in net/xfrm/xfrm_device.c NULL ->dev when releasing the reference on error. ref_tracker: reference already released. ref_tracker: allocated in: xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:86) ... udpv6_sendmsg (net/ipv6/udp.c:1696) ... ref_tracker: freed in: xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:90) ... WARNING: lib/ref_tracker.c:322 at ref_tracker_free+0x58b/0x780 dst_destroy (net/core/dst.c:115) rcu_core handle_softirqs ...

Package Linux Kernel

Published 2026-08-05

Last modified 2026-08-05

Patch available

Yes

Affected versions

Linux kernel versions 3.0.79, 3.2.46, 3.4.46, 3.9.3, 3.10 and later are affected. Fixed in 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2-rc4 and their respective stable series.

Affected from

≥ 3.0.79 ≥ 3.2.46 ≥ 3.4.46 ≥ 3.9.3 ≥ 3.10

Fixed in

✓ 6.6.148 6.6.x ✓ 6.12.101 6.12.x ✓ 6.18.42 6.18.x ✓ 7.1.6 7.1.x ✓ 7.2-rc4

References

5 total

Frequently asked questions

What is CVE-2026-64580?

CVE-2026-64580 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 3.0.79 onward and has been patched in 6.6.148, 6.12.101, 6.18.42 and others. CVE-2026-64580 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
Is there a patch available for CVE-2026-64580?

Yes. CVE-2026-64580 has been patched. Fixed versions include 6.6.148, 6.12.101, 6.18.42 and others. If you are running Linux kernel 3.0.79 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-64580 actively exploited?

No. CVE-2026-64580 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.