CVE-2026-100081
Received
Received - Intake
Linux Kernel Race Condition in Xen Netback
Vulnerability report for CVE-2026-100081, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-06
Last updated on: 2026-11-06
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
xen-netback: defer xenvif_mcast_addr_list_free()
In order for the function to legitimately avoid locking/RCU, it needs to
run after all TX/RX processing has finished/stopped: Lookups happen from
xenvif_start_xmit(), while adds/removes happen from xenvif_tx_action()
(called out of xenvif_poll()).
Move the call out of xenvif_disconnect_data() (the call to the function
from connect()'s error path doesn't require any cleaning up there), and
put it past the synchronization point in backend_disconnect().
This is XSA-527 / CVE-2026-100081.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| xen | xen_netback | From 4.3 (inc) |
| linux | linux | From 4.3 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |