PatchSiren cyber security CVE debrief
CVE-2026-64259 Linux CVE debrief
A Linux kernel vulnerability, CVE-2026-64259, was resolved by moving fuse_uring_add_to_pq() after copy operations to prevent use-after-free races. Malicious userspace could not find the request until all preparation work was completed. This change also avoided a forward declaration and facilitated easier backporting to older kernels. The vulnerability affects Linux kernel users and administrators, who should be aware of this vulnerability and take necessary actions to ensure their systems are updated.
- Vendor
- Linux
- Product
- Unknown
- CVSS
- Unknown
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-25
- Original CVE updated
- 2026-07-25
- Advisory published
- 2026-07-25
- Advisory updated
- 2026-07-25
Who should care
Linux kernel users and administrators should be aware of this vulnerability and take necessary actions to ensure their systems are updated. They should review system configurations for potential vulnerabilities, monitor system logs for suspicious activity, and plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
Technical summary
The Linux kernel vulnerability, CVE-2026-64259, was caused by a race condition in fuse-uring. The fix involved moving fuse_uring_add_to_pq() after memcpy operations to prevent use-after-free. This change ensured that malicious userspace could not prematurely access the request. The vulnerability has a medium defensive priority, and Linux kernel users and administrators should review system configurations for potential vulnerabilities and monitor system logs for suspicious activity.
Defensive priority
Medium
Recommended defensive actions
- Update Linux kernel to the latest version
- Review system configurations for potential vulnerabilities
- Monitor system logs for suspicious activity
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review compensating controls for exposed systems while remediation is scheduled and verified
- Check relevant monitoring, detection, and logs for exposed assets that need extra review
- Track exceptions, retest remediated assets, and close the item only after evidence is documented
Evidence notes
The CVE record was published on 2026-07-25T10:17:06.033Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official CVE record. The fix for this vulnerability involves moving fuse_uring_add_to_pq() after memcpy operations to prevent use-after-free races. Linux kernel users and administrators should review system configurations for potential vulnerabilities and monitor system logs for suspicious activity.
Official resources
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CVE-2026-64259 CVE record
CVE.org
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CVE-2026-64259 NVD detail
NVD
-
Source item URL
nvd_modified
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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Source reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-25T10:17:06.033Z and has not been modified since then.