CVE-2026-63989
Overview
CVE-2026-63989 is a known-severity vulnerability. It was published on July 19, 2026.
Technical Description
In the Linux kernel, the following vulnerability has been resolved:
bridge: Fix sleep in atomic context in netlink path
Since the introduction of the netlink configuration path for bridge
ports in commit 25c71c75ac87 ("bridge: bridge port parameters over
netlink"), br_setport() was always called with the bridge lock held
around it. Back then this decision made sense: The bridge lock protects
the STP state of the bridge and its ports and at that time the function
only processed three STP related netlink attributes (cost, priority and
state).
Nowadays, br_setport() processes a lot more attributes and most of them
do not need the bridge lock:
* Bridge flags: Only require RTNL. Read locklessly by the data path.
Annotations can be added in net-next.
* FDB port flushing: Only requires the FDB lock.
* Multicast attributes: Only require the multicast lock.
* Group forward mask: Only requires RTNL. Read locklessly by the data
path. Annotations can be added in net-next.
* Backup port
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Frequently Asked Questions
What is CVE-2026-63989?
CVE-2026-63989 is a known-severity vulnerability. It was published on July 19, 2026.
How severe is CVE-2026-63989?
CVSS score information is not yet available for this vulnerability. Check back as the CVE record is updated by NVD analysts.
How do I fix or remediate CVE-2026-63989?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-63989?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-63989 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
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