CVE-2020-16017

Exp

Use after free in site isolation in Google Chrome prior to 86.0.4240.198 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.

Published: 2021-01-08 Last update: 2025-10-24 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-16017 is rated Critical Active Threat (100/100): CVSS Critical severity, with high exploitation likelihood (EPSS 21.41%, 96th percentile). Core evidence: CISA KEV confirms active exploitation (added 2021-11-03) affecting Google / Chrome. a weakness (CWE-416) Unauthenticated remote administrative access may be possible. EPSS rose +4.47% over the last day, indicating growing attacker interest. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2020-16017

Name: Google Chrome Use-After-Free Vulnerability · CISA KEV detail

Exploit added: 2021-11-03

Action due: 2022-05-03

Required action: Apply updates per vendor instructions.

Exploit prediction scoring system (EPSS) score for CVE-2020-16017

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 2026-01-10 16.95% 21.41% +4.47%
2 2025-12-27 9.34% 16.95% +7.60%
3 2025-11-21 9.34%

Full EPSS history (23 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-16017

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 6.0 [email protected]
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 6.0 134c704f-9b21-4f2e-91b3-4a467353bcc0
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.6 6.4 [email protected]

Weakness enumeration for CVE-2020-16017

GitHub Security Advisory for CVE-2020-16017

OS Trackers for CVE-2020-16017

vendor priority summary link
debian not yet assigned CVE-2020-16017 not yet assigned priority: Debian including 1 source packages (chromium), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-16017
gentoo normal CVE-2020-16017: 1 GLSA(s) (202011-16), 2 atom(s) (www-client/chromium, www-client/google-chrome); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-16017
redhat high https://access.redhat.com/security/cve/CVE-2020-16017
ubuntu medium CVE-2020-16017 medium priority: Ubuntu including 1 source packages (chromium-browser), 6 status rows across 6 suites (bionic, focal, groovy, trusty, upstream, xenial): released 3, DNE 2, not-affected 1. https://ubuntu.com/security/CVE-2020-16017

Affected software / configurations for CVE-2020-16017

Vendor Product Version Raw CPE
google chrome < 86.0.4240.198 cpe:2.3:a:google:chrome:*:*:*:*:*:*:*:*

References for CVE-2020-16017

cvelogic Threat Intelligence