CVE-2023-35628 — Windows 10 21h2
HIGHCVE-2023-35628 is a high-severity (CVSS 8.1) Use After Free vulnerability in microsoft windows 10 21h2. EPSS puts its 30-day exploitation probability at 92.8% (100th percentile). A fix is available — see the affected versions and patch details below.
Windows MSHTML Platform Remote Code Execution Vulnerability
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-35628.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2023-35628 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 397,508 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Windows MSHTML Platform Remote Code Execution Vulnerability
Affected Products
windows 10 21h2microsoftwindows 10 22h2microsoftwindows 10 1507microsoftwindows 10 1607microsoftwindows 10 1809microsoftwindows 11 21h2microsoftDetection & mitigation playbook
Vendor / applianceDetect
Inventory every microsoft windows 10 21h2 deployment and check each version against the affected-products list above.
Fix
Apply the microsoft windows 10 21h2 security patch or hotfix for CVE-2023-35628 on the affected version, following the vendor advisory for your exact build.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2023-35628 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.