CVE-2017-0037 Microsoft Edge and Internet Explorer Type Confusion Vulnerability
Microsoft Edge and Internet Explorer have a type confusion vulnerability in mshtml.dll, which allows remote code execution.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 28 Mar 2022.
- Rated High severity (CVSS 8.1, scored by CISA).
- This product type is often exposed to the internet, which is where attackers scan for it first.
- It has been in the catalogue for 1,684 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Microsoft Internet Explorer 10 and 11 and Microsoft Edge have a type confusion issue in the Layout::MultiColumnBoxBuilder::HandleColumnBreakOnColumnSpanningElement function in mshtml.dll, which allows remote attackers to execute arbitrary code via vectors involving a crafted Cascading Style Sheets (CSS) token sequence and crafted JavaScript code that operates on a TH element.
Affected Versions
| Product | Versions |
|---|---|
| Microsoft Corporation Internet Browser | Internet Explorer 10 and 11 and Edge |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Microsoft Edge and Internet Explorer. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
- 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
Vendor Advisories
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2017-0037 and every other exploited flaw on the list.
Sources
- CISA Known Exploited Vulnerabilities catalogue
- NVD: CVE-2017-0037
- CVE record: CVE-2017-0037
- FIRST EPSS
- bugs.chromium.org/p/project-zero/issues/detail?id=1011
- 0patch.blogspot.si/2017/03/0patching-another-0-day-internet.html
- securityfocus.com/bid/96088
- exploit-db.com/exploits/41454/
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-0037
- exploit-db.com/exploits/43125/
- securitytracker.com/id/1037905
- exploit-db.com/exploits/42354/
