CVE-2026-49172
A critical flaw in the Windows FTP Service lets an attacker send specially crafted data that overflows a heap buffer, enabling them to run arbitrary code on the target machine. The vulnerability can be triggered over the network without any user interaction or special privileges.
No official fix yet. If none appears within 45 days of first tracking, this entry is removed automatically.
Who is affected
Microsoft Windows 10 (1607, 1809, 21H2, 22H2) and Windows 11 (23H2, 24H2, 25H2) – all builds that include the default FTP Service.
Real-world impact
An attacker who can reach the vulnerable FTP service can execute code with the same privileges as the service, potentially taking full control of the affected computer, installing malware, or exfiltrating data.
Why this severity
The CVSS score of 9.8 reflects that the flaw is exploitable over the network (AV:N), requires no authentication (PR:N), and has no user interaction (UI:N). It allows complete compromise of confidentiality, integrity, and availability, hence the critical rating.
What to do about it
No official fix or mitigation is documented in the sources yet. Monitor the vendor advisory and apply the patch as soon as it is released.
No fix documented in sources
Timeline
- Jul 14, 2026 · 20d agoPublishedDisclosed and added to the National Vulnerability Database.
- Jul 23, 2026 · 12d agoAdvisory updatedThe NVD record was last revised.
How it’s attacked
References & advisories
- msrc.microsoft.com/update-guide/vulnerability/…patchvendor advisory