CVE-2025-39963
- Published: 2025-10-09T13:15:32.517
In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix incorrect io_kiocb reference in io_link_skb
In io_link_skb function, there is a bug where prev_notif is incorrectly
assigned using ‘nd’ instead of ‘prev_nd’. This causes the context
validation check to compare the current notification with itself instead
of comparing it with the previous notification.
Fix by using the correct prev_nd parameter when obtaining prev_notif.
Related CVE by CWE
No related CWE found.
Top CVE for Vendor
No vendor taxonomy on this entry.
Recently Exploited Similar Vulnerabilities
No recent KEV-listed items for this vendor/product.
How to fix CVE-2025-39963
CVE-2025-39963 is a unknown severity vulnerability affecting the affected product.
Description: In the Linux kernel, the following vulnerability has been resolved: io_uring: fix incorrect io_kiocb reference in io_link_skb In io_link_skb function, there is a bug where prev_notif is incorrectly assigned using ‘nd’ instead of ‘prev_nd’. This causes the context validation check to compare the current notification with itself instead of comparing it with the previous notification. […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
- Check if you're running the affected product
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Description: In the Linux kernel, the following vulnerability has been resolved: io_uring: fix incorrect io_kiocb reference in io_link_skb In io_link_skb function, there is a bug where prev_notif is incorrectly assigned using ‘nd’ instead of ‘prev_nd’. This causes the context validation check to compare the current notification with itself instead of comparing it with the previous notification. […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
1 Identify affected systems
- Check if you're running the affected product
2 Immediate actions
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
3 Verification
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
4 Long-term prevention
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Exploit Difficulty Assessment
HARD
Time to Exploit: > 4 hours
Skills Required: Advanced security expertise
Public Exploits: Rare or not public
Vulnerability Timeline
Oct 09, 2025
Vulnerability Published
CVE details first published to NVD database
Nov 12, 2025
Imported to Database
Added to this CVE tracking system
Detection Rules & IOCs
No specific detection rules generated for this vulnerability type.
No vendor/product data available.