Cyber Resilience

CVE-2020-16017

Memory Safety in Google Chrome ≤ 86.0.4240.198

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
08 January 2021
Modified
24 October 2025
KEV Added
03 November 2021
Patch / advisory
View advisory
CVSS Score v3.1 9.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS Score 0.027 85th percentile
Risk Priority 94 floored blend · peak EPSS

Summary

CVE-2020-16017 is a critical-severity Use After Free (CWE-416) vulnerability in Google Chrome. Its CVSS base score is 9.6 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 15% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2020-16017 is a use-after-free vulnerability in the site isolation feature of Google Chrome versions prior to 86.0.4240.198. The flaw, tracked under CWE-416, resides in the browser's renderer process handling and carries a CVSS 3.1 score of 9.6, reflecting its high impact across confidentiality, integrity, and availability with changed scope.

A remote attacker who has already compromised the renderer process can exploit the issue by serving a crafted HTML page, enabling a sandbox escape that grants access to resources outside the intended renderer isolation boundaries. User interaction is required for successful exploitation.

Chrome stable channel updates released on 11 November 2020 address the vulnerability by updating to version 86.0.4240.198 or later. The flaw is also catalogued by CISA among known exploited vulnerabilities in the wild.

EU & UK References

Vulnerability Data

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.

CWE(s)
CWE-416
KEV Date Added
03 November 2021

Related Threats

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2019-5786Same product: Google Chromeboth on KEV
CVE-2020-6572Same product: Google Chromeboth on KEV
CVE-2021-4102Same product: Google Chromeboth on KEV
CVE-2022-0609Same product: Google Chromeboth on KEV
CVE-2025-5068Same product: Google Chrome
CVE-2024-3169Same product: Google Chrome
CVE-2023-6704Same product: Google Chrome
CVE-2024-10827Same product: Google Chrome
CVE-2025-5958Same product: Google Chrome
CVE-2024-6103Same product: Google Chrome

Affected Assets

google
chrome
≤ 86.0.4240.198

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect use-after-free bugs before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

A.8.32 Change management partial match
prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248592 OL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 8 (1 rule)
  • V-230279 RHEL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 9 (1 rule)
  • V-257794 RHEL 9 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416

References