Google Chrome Use-After-Free Vulnerability
Google · Chrome
A use-after-free flaw in the site isolation component of Google Chrome (versions prior to 86.0.4240.198) can be exploited by a remote attacker who has already compromised the renderer process. An attacker who has achieved renderer compromise and can get a victim to load a crafted HTML page could potentially escape the sandbox.
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.
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.How attackers get in
What they do
Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 2 months before it was disclosed.
- First seen exploitedVulnCheck KEV evidence2 mo before
- Disclosedday 0
- Added to CISA KEVEU database agrees+10 mo
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
2 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order, 2 cited passages 2Initial AccessTA0001
Malicious webpage delivered to victim browser
via a crafted HTML page
Privilege EscalationTA0004
Escapes renderer sandbox to host context
potentially perform a sandbox escape
Detection
0 rules for this CVE · 5 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2020-16017 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Drive-by CompromiseT11893 general rules
Escape to HostT16112 general rules
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
Am I affected? What do I upgrade to?
From GitHub Security Advisories and OSV4 packages in 1 ecosystem. No single main package: each of these ships the affected code.
- NuGetCefSharp.CommonAffected: All versions before 86.0.241Upgrade to 86.0.241 or later
- NuGetCefSharp.WpfAffected: All versions before 86.0.241Upgrade to 86.0.241 or later
- NuGetCefSharp.WinFormsAffected: All versions before 86.0.241Upgrade to 86.0.241 or later
- NuGetCefSharp.Wpf.HwndHostAffected: All versions before 86.0.241Upgrade to 86.0.241 or later
What security researchers reported
Not named in any threat report yetAlso mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
- 44 more on OTX