Use After Free in Microsoft Edge
CVE-2021-26411
Internet Explorer Memory Corruption Vulnerability
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L.
EPSS exploit prediction
EPSS: 0.808 (99.6th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.808 · newest: 0.808 · change: 0.000
Affected products
- Microsoft Edge
- Microsoft Internet Explorer — versions 11, 9
- Microsoft Internet Explorer 11 — versions 1.0.0
- Microsoft Internet Explorer 9 — versions 1.0.0
- Microsoft Edge (Edgehtml-Based) — versions 1.0..0
- Microsoft Windows 10 1507
- Microsoft Windows 10 1607
- Microsoft Windows 10 1803
- Microsoft Windows 10 1809
- Microsoft Windows 10 1909
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
Required action: Apply updates per vendor instructions.
Known ransomware campaign use: yes.
Public proof-of-concept exploits
References
- af854a3a-2127-422b-91ae-364da2661108 (Patch, Vendor Advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
- msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26411 (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-26411?
- CVE-2021-26411 is a high-severity vulnerability in Microsoft Edge, classified under Use After Free. CVSS score: 8.8/10. Published 2021-03-11.
- How severe is CVE-2021-26411?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2021-26411 known to be exploited?
- Yes. CVE-2021-26411 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 14 public proof-of-concept repositories are indexed.