CVE-2020-0878Microsoft Browser Memory Corruption Vulnerability
Updated under an hour ago ()
Does this affect you?
It affects Microsoft ChakraCore and 2 other products. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Nov 3, 2021; federal agencies had to remediate by May 3, 2022, and it is known to be used in ransomware. Treat that date as your deadline.
Do this next
Free account, 1 product
<p>A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to 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, the attacker 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.</p> <p>An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft browsers, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically via an enticement in email or instant message, or by getting them to open an email attachment.</p> <p>The security update addresses the vulnerability by modifying how Microsoft browsers handle objects in memory.</p>
- CVSS
- 4.2 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C
- Weakness (CWE)
- CWE-787
- Known exploited
- Added to CISA KEV Nov 3, 2021; federal remediation due May 3, 2022; known ransomware useApply updates per vendor instructions.
- EPSS (exploitation in the next 30 days)
- 2.70% (percentile 86)
- Assigned by
- microsoft
- NVD analysis
- Analyzed
- Record last updated
- Oct 21, 2025
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Microsoft ChakraCore microsoft:chakracore | before publication | CNA record |
Microsoft Microsoft Edge (EdgeHTML-based) microsoft:edge | from 1.0..0 before publication | CNA record |
Microsoft Internet Explorer 9 microsoft:internet_explorer | from 1.0.0 before publication | CNA record |
microsoft internet_explorer microsoft:internet_explorer | 11; 9 | NVD |
microsoft edge microsoft:edge | all versions | NVD |
microsoft chakracore microsoft:chakracore | all versions | NVD |
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0878x-refsource-misc, patch, vendor-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0878us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.