What’s Vulnerable › Vulnerabilities

CVE-2026-98251: openvswitch: avoid reallocating confirmed conntrack labels

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-06 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: openvswitch: avoid reallocating confirmed conntrack labels ovs_ct_get_conn_labels() adds the labels extension when a conntrack entry does not have one. Confirmed conntracks can be read locklessly, so adding an extension may reallocate and free the extension block while another CPU accesses it. Only add the extension for unconfirmed conntracks. A confirmed conntrack without labels now fails the caller's label operation instead of reallocating its extension storage.

Affected products

• Linux kernel: 4.3 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/05eab8dced6bf4d3009a6eeee16ddac99047dc83
• https://git.kernel.org/stable/c/2e6dd889c325abf23821e1459c3ffef59b7f0009
• https://git.kernel.org/stable/c/3f118c8217c109fd13ca61caa301d72c483897ef
• https://git.kernel.org/stable/c/4371d79ea74407fb992c985b1f94391e35bb8289
• https://git.kernel.org/stable/c/579d87ec1e1e85729a6cb2c25961e58beb78640c
• https://git.kernel.org/stable/c/7ff688aceada1160331a789385ea146f62fbddf7
• https://git.kernel.org/stable/c/8c9fcc6c33950d3db551af664d1fd3d998bfee56
• https://git.kernel.org/stable/c/d16f089bd700f45d720ce989d5495e1dc3be0cf8

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