A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Microsoft Edge (HTML-based). The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge (HTML-based) and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how the scripting engine handles objects in memory.
Conclusion & alert: CVE-2020-1555 is rated Moderate Risk (63/100): CVSS High severity, with high exploitation likelihood (EPSS 14.47%, 94th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2025-03-30 | 48.30% | 14.47% | -33.83% |
| 2 | 2025-03-29 | 14.47% | 48.30% | +33.83% |
| 3 | 2025-03-17 | — | 14.47% | — |
Full EPSS history (21 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| 9.3 | 2.0 | HIGH |
|
8.6 | 10.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| microsoft | edge | — | cpe:2.3:a:microsoft:edge:-:*:*:*:*:*:*:* |
| microsoft | chakracore | — | cpe:2.3:a:microsoft:chakracore:-:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1555 | Patch Vendor Advisory |