A kernel-level issue
The CVE-2026-98432 record was published on 15 October 2026. The issue concerns memory use when processing certain TCP IPv4 connections: a memory region can be freed while another processor is still reading it. This type of error is called use-after-free.
The fix described in the record changes when that memory is freed, taking account of readers that may still be using it. This is not an error in the website theme and cannot be resolved with a simple plugin update.
Why risk assessments can be different
When the sources were checked, Ubuntu listed High priority and a CVSS 3 score of 9.8. Red Hat published a CVSS 3.1 score of 8.1 and indicated high attack complexity. Its description highlighted the risk of a system crash and possible memory corruption.
These assessments must be read in the context of the product and the vendor’s analysis. They justify neither ignoring the update nor concluding that every Linux server can immediately be taken over remotely.
| Vendor | Priority / severity | Published Score |
|---|---|---|
| Ubuntu | High / Critical CVSS | 9,8 |
| Red Hat | High CVSS | 8,1 |
Check the exact distribution and package
Patch status varies between distributions, versions and kernel variants. A version number alone may be insufficient: vendors can integrate a fix into a package while retaining part of its existing version numbering.
Before making changes, we recommend listing the operating system, installed package, running kernel and applicable security bulletin. This lets the administrator track which servers have been checked and which are still awaiting a patched package.
Identify the system and running kernel
On Linux, these commands display the distribution and running kernel version. They provide a starting point for the inventory before comparing the package against the distribution’s security announcement.
cat /etc/os-release
uname -rIn containers, os-release describes the container environment, while uname reflects the host kernel. Recording the version does not confirm that the fix has been applied; check the package and any fixes integrated by the vendor.
Check both the installed package and the running kernel
We recommend planning the update together with the activation procedure specified by the vendor. Restarting a web service does not automatically replace the running kernel.
A complete intervention includes a maintenance window, a recovery access route and checks after activation. On systems offering live patching, explicitly confirm coverage of this vulnerability, rather than merely checking that the service exists.
- Consult the distribution’s CVE page for the product and package in use.
- Prepare the backup, recovery access and rollback procedure.
- Apply the recommended package and activate the fix using the vendor’s procedure.
- Confirm the running kernel and service status after the update.
- Monitor errors, unexpected restarts and application availability.
Application and system security complement each other
A WAF analyses the traffic of the application, while the problem discussed here is in the TCP processing of the kernel. Therefore, a WAF rule should not be presented as proof that the system has been corrected.
Limiting service exposure and monitoring remain useful measures. Keep temporary mitigations, the patched package and evidence that the fix is active separate in the intervention record. This makes the report easy to verify, even after responsibility for operating the server changes.
Sources and verification
The technical information was checked on 31 October 2026. Package status and vendor recommendations can change; consult the current announcement for the product in use before making changes.