CVE-2026-49415 FreeBSD CVE debrief

Who should care

System administrators, security teams, and developers responsible for maintaining systems with SUID binaries, particularly those using FreeBSD, should be aware of this vulnerability. They should review their system configurations, verify and apply patches, and monitor system logs for suspicious activity. Additionally, they should consider implementing compensating controls to limit access to SUID binaries and perform regular inventory checks for affected systems.

Technical summary

During execve(2) of a SUID binary, the new virtual address space is installed before process credentials are updated. An unprivileged local user can access the target process's memory via procfs or linprocfs during this window, allowing exploitation of a race condition to modify the address space of a SUID binary before its credentials are elevated. This can potentially lead to full control of the affected system. The exploitation of this vulnerability requires local access and the ability to execute code on the affected system.

Defensive priority

High priority due to potential for privilege escalation

Recommended defensive actions

• Verify and apply vendor patches or updates
• Implement compensating controls to limit access to SUID binaries
• Monitor system logs for suspicious activity
• Perform regular inventory checks for affected systems
• Review system configurations for SUID binary usage
• Check for and apply any additional security updates or patches
• Track and verify system changes related to this vulnerability

Evidence notes

Evidence from FreeBSD security advisory and NVD vulnerability detail page. Limited information available on affected scope and vendor remediation. The vulnerability is caused by a race condition during execve(2) of a SUID binary, allowing an unprivileged local user to access the target process's memory via procfs or linprocfs. To verify, defenders should review FreeBSD security advisories, NVD details, and system logs for suspicious activity related to SUID binaries and procfs/linprocfs access.

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.