CVE-2021-21148VulnerabilityPublished 11/03/2021Updated 10/24/2026

CVE-2021-21148: Google Chromium V8 Heap Buffer Overflow Vulnerability

Affects Google Chromium V8Source CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 11/03/2021
KEV deadline: 11/17/2021
EPSS: 20.0% chance of exploitation in 30 days – higher than 97% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2021-21148 (opens in a new tab)

Description

CVE-2021-21148 is a heap buffer overflow vulnerability in the Google Chromium V8 JavaScript engine. It allows a remote attacker to cause heap corruption by crafting a malicious HTML page. This vulnerability affects multiple Chromium-based browsers such as Google Chrome, Microsoft Edge, and Opera. It has been exploited in the wild. No specific affected versions or patch information is provided in the input data.

Summary

The vulnerability CVE-2021-21148 exists in the Google Chromium V8 engine and is classified as a heap buffer overflow (CWE-122). A remote attacker can exploit this flaw by delivering a specially crafted HTML page that triggers heap corruption in the V8 engine. This issue impacts multiple browsers built on Chromium, including Google Chrome, Microsoft Edge, and Opera. The vulnerability has been observed in active exploitation campaigns. However, no patch or remediation details are included in the provided information.

Impact

Successful exploitation of this vulnerability can lead to heap corruption, which may allow an attacker to execute arbitrary code or cause a denial of service in affected Chromium-based browsers. The vulnerability is known to be exploited in the wild, indicating active threat and potential risk to users of vulnerable browsers.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users and administrators should monitor official Google Chromium security advisories for updates and apply patches promptly once available.

Weaknesses

CWE-122Heap-based Buffer Overflow (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 09:26:05 UTC

Weaknesses

References

Related threats