{"id":"CVE-2026-64580","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-64580","summary":"xfrm6: clear dst.dev on error to avoid double netdev_put in xfrm6_fill_dst()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm6: clear dst.dev on error to avoid double netdev_put in xfrm6_fill_dst()\n\nOn the error path where in6_dev_get(dev) returns NULL, xfrm6_fill_dst()\nreleases the device reference with netdev_put() but leaves\nxdst->u.dst.dev set. dst_destroy() later calls netdev_put(dst->dev)\nagain, so the same net_device reference is released twice, underflowing\nits refcount (ref_tracker WARNING + \"unregister_netdevice: waiting for\n<dev> to become free\").\n\nClear xdst->u.dst.dev after the netdev_put(), the same way the XFRM\ndevice-offload paths xfrm_dev_state_add() and xfrm_dev_policy_add() in\nnet/xfrm/xfrm_device.c NULL ->dev when releasing the reference on error.\n\n  ref_tracker: reference already released.\n  ref_tracker: allocated in:\n   xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:86)\n   ...\n   udpv6_sendmsg (net/ipv6/udp.c:1696)\n   ...\n  ref_tracker: freed in:\n   xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:90)\n   ...\n  WARNING: lib/ref_tracker.c:322 at ref_tracker_free+0x58b/0x780\n   dst_destroy (net/core/dst.c:115)\n   rcu_core\n   handle_softirqs\n   ...","published":"2026-08-05T08:09:34.946Z","modified":"2026-08-07T03:45:39.580259622Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.148"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/136992de9bb91871084ae52d172610541c76e4d2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/43de8a49335e611adb271bbd52e84dfbc11fc185"},{"type":"WEB","url":"https://git.kernel.org/stable/c/df6856c2dda9187601d29b5fbd7a81b3b178cedf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e078da1b4e11390cff3201c19a9a1fe70c5b934f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ff636d7b7cba6dea82ecf580415ea57f2c1a11b6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64580.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64580"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T03:45:39.580259622Z"}}