CVE-2021-21206: Google Chromium Blink Use-After-Free Vulnerability
Vulnerability summary
CVE-2021-21206 is a high (CVSS 8.8) Use After Free vulnerability in Google Chromium Blink. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 9.31% chance of exploitation in the next 30 days, higher than 95.3% of scored vulnerabilities.
Listed as exploited by CISA (03-11-2021)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 5 · Related 5Timeline
- 26-04-2021PublishedVulnerability first disclosed.
- 03-11-2021Added to CISA KEVExploitedGoogle Chromium Blink Use-After-Free Vulnerability
- 17-11-2021CISA remediation dueDeadline passedApply updates per vendor instructions.
- 21-10-2025Last modifiedVulnerability information updated.
Description
Use after free in Blink in Google Chrome prior to 89.0.4389.128 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
CVSS metrics
6 scores · 5 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- NVDNIST8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- OSV · AlpineEcosystem advisory · calculated8.8HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
9.31%
Chance of exploitation in the next 30 days
Percentile
95%
Versus all other CVEs
30-day change
No change 0.00 pp
From 9.31% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVListed- Added
- 03-11-2021
- Federal due date
- 17-11-2021
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
CISA required action
Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2021-21206
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine2 products
- chromium< 89.0.4389.128-r0
- qt5-qtwebengine< 5.15.3_git20210510-r0
Debian1 product
- chromium< 90.0.4430.72-1
Fedoraproject1 product
- fedoraEOL32 | 33 | 34
Google1 product
- chrome≥ unspecified, < 89.0.4389.128 | < 89.0.4389.128
Ubuntu1 product
- chromium-browser< 90.0.4430.72-0ubuntu0.16.04.1 | < 90.0.4430.72-0ubuntu0.18.04.1
5 vendors · 6 products
References
12 links- chromereleases.googleblog.com/2021/04/stable-channel-update-for-desktop.htmlX Refsource MISCRelease Notes
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21206Government ResourceUS Government Resource
