CVE-2019-1429: Internet Explorer scripting engine memory corruption RCE

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 17 September 2026. Confidence: high.

high priorityConfirmed in-the-wild exploitation (KEV) and very high EPSS, but exploitation requires user interaction and is rated high complexity.

What it is

Internet Explorer's scripting engine mishandles objects in memory, producing a use-after-free and out-of-bounds write (CWE-416, CWE-787). A remote attacker can corrupt memory and execute code in the context of the browser, which matters because IE is still present on many Windows systems and this flaw was exploited in the wild.

Impact

Successful exploitation gives the attacker remote code execution at the privilege level of the IE process, enabling arbitrary code, data theft or further host compromise.

Attack surface

Reached over the network (AV:N) with no privileges required (PR:N), but the victim must interact with a crafted page or document (UI:R), and the attack is rated high complexity (AC:H).

Exploitation

Listed in CISA KEV since 2021-11-03 with a required action to patch, and EPSS is 0.7729 (99.5th percentile); a public exploit reference exists, so exploitation is confirmed and active.

What to do

• Apply the Microsoft security update for CVE-2019-1429 (patch first).
• Disable or remove Internet Explorer where possible and block IE rendering of untrusted content.
• Restrict browsing to trusted sites and enforce network controls against known exploit delivery hosts.
• Keep Windows and browser components fully patched to close related scripting engine flaws.

Detection

• Hunt for IE (iexplore.exe) spawning child processes such as cmd.exe, powershell.exe or script hosts.
• Monitor for crashes or unusual memory behavior in iexplore.exe tied to script execution.
• Alert on network fetches of known exploit pages or payloads matching the public exploit reference.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.