CVE-2026-98490 Linux CVE debrief

Who should care

Linux kernel maintainers, administrators, and users of Linux systems with Open vSwitch conntrack enabled should assess exposure and prioritize verification of kernel versions in use.

Why it matters

A use-after-free vulnerability in the Linux kernel's Open vSwitch conntrack implementation can cause issues if exploited. Assess exposure and prioritize verification of Linux kernel versions in use.

• Verify Linux kernel versions in use and apply patches if available
• Assess exposure and prioritize verification of Open vSwitch conntrack enabled systems

Technical summary

The Linux kernel's Open vSwitch conntrack implementation has a use-after-free vulnerability. When calling helpers, a raw pointer to the extensions area is stored in the expectations list. If the connection is not confirmed yet, more extensions can be added later, reallocating the extension space and leaving the invalid pointer in the expectations list. This can cause a use-after-free when removing the expectation. The vulnerability was resolved by making sure that helpers are called at the end after all the other extensions are already added.

Defensive priority

Assess exposure and prioritize verification of Linux kernel versions in use, focusing on those with Open vSwitch conntrack enabled.

Recommended defensive actions

• Assess Linux kernel versions in use and verify if Open vSwitch conntrack is enabled
• Prioritize verification of kernel versions and apply patches if available
• Monitor for potential exploitation attempts
• 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
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but do not specify affected or fixed versions. Linux kernel maintainers have resolved the issue. The vulnerability was found in the Linux kernel's Open vSwitch conntrack implementation. A use-after-free vulnerability can cause issues if exploited. Assess exposure and prioritize verification of Linux kernel versions in use, focusing on those with Open vSwitch conntrack enabled. Evidence is limited, and defenders should verify kernel versions and apply patches if

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.