CVE-2026-72405 (GCVE-0-2026-72405)
Vulnerability from cvelistv5
Published
2026-08-15 05:56
Modified
2026-10-21 12:44
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net: udp_tunnel: prevent double queueing in udp_tunnel_nic_device_sync Yue Sun reported a use-after-free and debugobjects warning in udp_tunnel_nic_device_sync_work() during concurrent device operations. The workqueue core clears the internal pending bit before invoking the worker. At that point, a concurrent thread can queue the work again. When the already running worker eventually clears the work_pending flag to 0, it mistakenly clears the flag for the newly queued instance. udp_tunnel_nic_unregister() then observes work_pending as 0 and frees the structure while the second work item is still active in the queue, leading to UAF. Fix this by returning early in udp_tunnel_nic_device_sync() if work_pending is already set, preventing redundant work queueing.
References
Impacted products
Vendor Product Version
Linux Linux Version: cc4e3835eff474aa274d6e1d18f69d9d296d3b76
Version: cc4e3835eff474aa274d6e1d18f69d9d296d3b76
Version: cc4e3835eff474aa274d6e1d18f69d9d296d3b76
Version: cc4e3835eff474aa274d6e1d18f69d9d296d3b76
Version: cc4e3835eff474aa274d6e1d18f69d9d296d3b76
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