CVE-2021-28691

Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.

• CWE-416

• https://security.gentoo.org/glsa/202107-30Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210805-0002/Third Party Advisory
• https://xenbits.xenproject.org/xsa/advisory-374.txtThird Party Advisory
• https://security.gentoo.org/glsa/202107-30Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210805-0002/Third Party Advisory
• https://xenbits.xenproject.org/xsa/advisory-374.txtThird Party Advisory

Published

Jun 29, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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