Kernel crash via freed flow mask access
Published Sep 11, 2026 · Updated Sep 11, 2026
Use-after-free in Linux Open vSwitch flow deletion allows local users with CAP_NET_ADMIN to crash the kernel through a timing race. ovs_flow_cmd_del removes a flow before ovs_flow_cmd_fill_info reads flow->mask, allowing an RCU grace period to free the mask first. Reaching the flaw requires a privileged OVS_FLOW_CMD_DEL operation and favorable race timing; the demonstrated consequence is a host kernel crash.
Summary
What happened
Use-after-free in Linux Open vSwitch flow deletion allows local users with CAP_NET_ADMIN to crash the kernel through a timing race. ovs_flow_cmd_del removes a flow before ovs_flow_cmd_fill_info reads flow->mask, allowing an RCU grace period to free the mask first. Reaching the flaw requires a privileged OVS_FLOW_CMD_DEL operation and favorable race timing; the demonstrated consequence is a host kernel crash.
The record
- CVE
- CVE-2026-80994
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1499.004
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3.16
- Affected versionversion=56c19868e115fcf8d62d843e1b9616bb9837d0db <0ba5cbc2f049af94ec94ff6f64958545efc5eaa2
- Affected versionversion=56c19868e115fcf8d62d843e1b9616bb9837d0db <4e30317ff67a2eb12b4d890d39f72fd7e7117d48
- Affected versionversion=56c19868e115fcf8d62d843e1b9616bb9837d0db <7f072b84afd05a77963eb1872f7174e280661dce
- Affected versionversion=56c19868e115fcf8d62d843e1b9616bb9837d0db <ac73e3af571da06c1d1cfe3f0f00dc978b851700
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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