CVE-2026-106220

Executive Summary

CVE-2026-106220 is an information leak vulnerability in the password handling component of Google Chrome versions prior to 155.0.8059.39. A remote attacker can exploit this flaw by luring a user to a crafted HTML page, potentially disclosing sensitive information such as stored credentials or password-related data. With a CVSS score of 8.8, the vulnerability carries a high severity rating, though the Chromium security severity is classified as Low. No public proof-of-concept or exploit code is currently available, and the issue remains unpatched in versions below the fixed release.

Technical Analysis

The vulnerability resides within the password management subsystem of Google Chrome. According to the NVD description, it is classified as an information leak (CWE-200) that can be triggered via a crafted HTML page. The attack vector is network-based (AV:N), requires low attack complexity (AC:L), no privileges (PR:N), and user interaction (UI:R) — specifically, the victim must visit a malicious or compromised web page. The CVSS vector indicates high confidentiality impact (C:H), high integrity impact (C:H), and high availability impact (A:H), suggesting the flaw could lead to unauthorized access to sensitive data and potentially affect the integrity and availability of the browser or its stored information.

The exact mechanism of the information leak is not detailed in the available description. However, based on the vulnerability class (CWE-200) and the context of "Passwords" in Chrome, it likely involves improper handling of password data when rendering or processing HTML content. The Chromium security severity is rated Low, which may indicate that the leak is limited in scope or requires specific conditions to exploit, yet the CVSS score of 8.8 reflects a more severe potential impact in enterprise environments where Chrome is widely deployed.

No specific function names, API endpoints, or file paths are provided in the NVD description or CNA title. Therefore, the technical analysis must remain at the class level: an information disclosure flaw in the password component that is remotely triggerable via a web page. The lack of public details suggests the vulnerability may be newly disclosed or still under analysis.

Exploitation Scenarios

No public proof-of-concept or exploit code is available for CVE-2026-106220. The attack chain is inferred from the vulnerability class (information leak) and the required user interaction.

1. Reconnaissance/target identification: An attacker identifies targets running Google Chrome versions prior to 155.0.8059.39. This could be done through browser fingerprinting, user-agent strings, or known vulnerable populations in enterprise environments.

2. Triggering the flaw: The attacker crafts a malicious HTML page designed to exploit the password information leak. The specific technique is not disclosed, but based on the class, it likely involves JavaScript or HTML elements that cause Chrome to improperly expose password data — for example, through side-channel leaks, improper autofill behavior, or rendering flaws. The victim must navigate to this page using the vulnerable browser.

3. Payload/execution method: The crafted HTML page is hosted on an attacker-controlled domain or injected into a compromised legitimate site. The page's code triggers the information leak without requiring additional plugins or extensions. The exact payload structure is unknown, but it operates within the browser's standard web content execution context.

4. Post-exploitation impact: Successful exploitation could allow the attacker to obtain sensitive information such as saved passwords, autofill data, or other credentials stored in Chrome's password manager. This data could then be exfiltrated to the attacker's server, enabling account takeover, lateral movement, or further compromise of the victim's digital identity.

Impact Assessment

The vulnerability affects all users of Google Chrome versions prior to 155.0.8059.39 across all supported operating systems and platforms. Given Chrome's dominant market share, the blast radius is extremely large. The CVSS score of 8.8 (High) indicates a severe risk, with high confidentiality, integrity, and availability impacts. However, the Chromium security severity rating of Low suggests that the practical exploitation may be constrained or require specific conditions.

Business impact includes potential exposure of corporate credentials stored in Chrome's password manager, leading to unauthorized access to enterprise applications, data breaches, and compliance violations (e.g., GDPR, HIPAA). The high integrity and availability impacts imply that an attacker could not only read sensitive data but also potentially modify or disrupt browser functionality. The user interaction requirement (UI:R) means exploitation relies on social engineering, but the low complexity (AC:L) and no privileges (PR:N) make it attractive to a broad range of attackers.

No CISA KEV listing and no known active exploitation in the wild have been reported as of this writing. The EPSS score is not yet available.

Detection Guidance

Sigma Rule

title: Potential Chrome Password Information Leak Exploitation Attempt
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects crafted HTML pages attempting to exploit CVE-2026-106220 in Google Chrome versions prior to 155.0.8059.39
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-106220
author: Threat Intelligence Team
date: 2026/05/20
tags:
    - attack.t1204.001
    - attack.collection
logsource:
    category: process_creation
    product: windows
detection:
    selection_browser:
        Image|endswith:
            - '\chrome.exe'
            - '\chromium.exe'
    selection_cmdline:
        CommandLine|contains:
            - '--disable-web-security'
            - '--allow-running-insecure-content'
            - '--user-data-dir'
    condition: selection_browser and selection_cmdline
falsepositives:
    - Legitimate developer testing
level: medium

YARA Rule

rule CVE_2026_106220_Chrome_Password_Leak
{
    meta:
        description = "Detects HTML content attempting to exploit CVE-2026-106220"
        author = "Threat Intelligence Team"
        date = "2026-05-20"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-106220"
        severity = "high"
    strings:
        $html1 = "<input type=\"password\"" ascii nocase
        $html2 = "autocomplete=\"current-password\"" ascii nocase
        $html3 = "autocomplete=\"new-password\"" ascii nocase
        $js1 = "document.querySelector" ascii nocase
        $js2 = "getComputedStyle" ascii nocase
        $js3 = "performance.now" ascii nocase
        $js4 = "MutationObserver" ascii nocase
        $exfil1 = "fetch(" ascii nocase
        $exfil2 = "XMLHttpRequest" ascii nocase
        $exfil3 = "navigator.sendBeacon" ascii nocase
    condition:
        (2 of ($html*)) and (2 of ($js*)) and (1 of ($exfil*))
}

Suricata IDS Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2026-106220 Google Chrome Password Information Leak Attempt"; flow:to_server,established; content:"POST"; http_method; content:"|0d 0a|"; content:"password"; http_client_body; nocase; content:"autocomplete"; http_client_body; nocase; pcre:"/fetch|XMLHttpRequest|sendBeacon/i"; threshold:type limit, track by_src, count 1, seconds 60; reference:cve,2026-106220; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-106220; classtype:attempted-user; sid:2026106220; rev:1;)

Elastic Detection

process where event.type == "start" and
  process.name : ("chrome.exe", "chromium.exe", "google-chrome", "chromium") and
  process.args : ("--disable-web-security", "--allow-running-insecure-content") and
  process.parent.name : ("explorer.exe", "bash", "zsh", "cmd.exe")

Splunk SPL Query

index=proxy OR index=web
| search (uri_path="*.html" OR uri_path="*.htm")
| rex field=uri_query "(?<param>password|autocomplete|credential)"
| search param=*
| stats count by src_ip, dest_host, uri_path, user_agent
| where count > 5
| sort - count

Wazuh OSSEC Rule

<group name="web,chrome,cve-2026-106220">
  <rule id="100220" level="10">
    <if_sid>31100</if_sid>
    <field name="url">\.html|\.htm</field>
    <field name="user_agent">Chrome/(1[0-4][0-9]|15[0-4])\.</field>
    <description>CVE-2026-106220: Potential Chrome password information leak exploitation attempt</description>
    <mitre>
      <id>T1204.001</id>
    </mitre>
    <group>cve_2026_106220,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source).

1. Immediate mitigations:

   • Enforce browser isolation or sandboxing for all web browsing activities.
   • Disable or restrict Chrome's password manager via enterprise policy (e.g., PasswordManagerEnabled=false).
   • Implement network-level filtering to block known malicious domains and suspicious HTML content.
   • Educate users on phishing and social engineering risks, emphasizing not to visit untrusted links.

2. Patch/upgrade steps:

   • Upgrade Google Chrome to version 155.0.8059.39 or later as soon as it becomes available.
   • Verify the update through Chrome's official release channels or enterprise deployment tools.
   • Monitor Google's Chrome Releases blog and Chromium security advisories for the official patch.

3. Long-term hardening:

   • Adopt a rapid patch management cycle for all browsers, with automatic updates enabled where feasible.
   • Deploy endpoint detection and response (EDR) solutions capable of monitoring browser process behavior.
   • Implement application allowlisting to prevent unauthorized browser extensions or modifications.
   • Conduct regular security awareness training focused on web-based threats and credential hygiene.
   • Consider using enterprise password managers that are separate from browser-integrated stores.

References

• NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2026-106220
• Google Chrome Releases: https://chromereleases.googleblog.com/
• Chromium Security Advisories: https://www.chromium.org/Home/chromium-security/
• CWE-200: Information Exposure: https://cwe.mitre.org/data/definitions/200.html
• MITRE ATT&CK T1204.001: https://attack.mitre.org/techniques/T1204/001/