CRITICAL

CVE-2021-21155

CVSS v3

9.6

CRITICAL

EPSS Score

1.3 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

CVE-2021-21155 Red Hat Product Security
chromium-browser: Heap buffer overflow in Tab Strip

Full record on NVD

Description

Heap buffer overflow in Tab Strip in Google Chrome on Windows prior to 88.0.4324.182 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.

Technical details

Published: 2021-02-22

Frequently asked questions

What is CVE-2021-21155?

Is CVE-2021-21155 actively exploited?

Active exploitation of CVE-2021-21155 has not been confirmed. Its EPSS score was 1.3% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-21155?

CVE-2021-21155 has a CVSS v3 base score of 9.6 (CRITICAL severity).

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