Skip to main content

Google Chrome CVE-2026-121104

| EUVDEUVD-2026-116430 CRITICAL
Incorrect Authorization (CWE-863)
2026-11-03 Chrome GHSA-q6c8-8mv6-7jfq
9.6
CVSS 3.1 · Vendor: Chrome
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Lure victim to malicious site
  2. Delivery
    Serve crafted HTML page
  3. Exploit
    Trigger FileSystem authorization flaw
  4. Execution
    Escape renderer sandbox
  5. Impact
    Execute arbitrary code on host

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Authorization logic validation
MITRE ATT&CK

1 technique across 1 tactic: Privilege Escalation

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Exploitation Conditions

Exploitation requires a victim running Google Chrome desktop prior to 157.0.8103.38 to be socially engineered into visiting or opening an attacker-crafted HTML page (UI:R) - there is no authentication requirement (PR:N) and it works against default Chrome configurations. The limiting factor is the mandatory user interaction: the attacker cannot trigger it without luring the user to malicious web content, so it is not wormable or drive-by without that lure. The specific FileSystem feature/configuration abused and the exact authorization check that fails are not detailed in the available sources.

Impact

Multiple signals align toward genuine high priority. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H, base 9.6) describes a network-reachable, low-complexity, unauthenticated flaw whose only gating factor is user interaction, and the changed scope (S:C) reflects a sandbox escape - the browser sandbox boundary is crossed to impact the host. The vendor-tagged Chromium severity is High and the vuln.today Decision label is act_now, and a vendor patch is already available, so remediation should be treated as urgent. Countervailing context: this is NOT listed in CISA KEV in the provided data, and no EPSS score was supplied, so there is no confirmation of active or widespread exploitation - the act_now urgency is driven by the severity, scope change, and patch availability rather than by observed in-the-wild use. The only exploit-adjacent reference is the Chromium issue tracker entry (issues.chromium.org/577400245), which is typically access-restricted and is NOT a working public exploit. CWE-863 (Incorrect Authorization) and the description ('Incorrect authorization in FileSystem') indicate an authorization logic flaw, which is more precise than the input's 'Authentication Bypass' tag; treat the mechanism as an authorization check failure in the FileSystem component, not a credential bypass.

Exploit ScenarioDerived

An attacker uses social engineering (phishing link, malicious ad, or compromised site) to lure a victim running a pre-157.0.8103.38 Chrome build into opening a crafted HTML page. The page abuses the FileSystem incorrect-authorization flaw to break out of the renderer sandbox and run attacker code in the host context. No public working exploit was identified; only a (typically restricted) Chromium bug-tracker reference exists.

Act Now Prioritize within 24-48h. Why: CRITICAL severity.
Patch available

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Nov 03, 2026

Incorrect authorization in the FileSystem component of Google Chrome (all desktop versions prior to 157.0.8103.38) allows a remote, unauthenticated attacker to execute arbitrary code outside the browser sandbox, provided the victim is socially engineered into visiting or opening a crafted HTML page. The attack is not self-propagating: exploitation is gated entirely by the required user interaction (UI:R), but against a lured victim it works on default configurations and, per the CVSS scope-change metric, can compromise resources beyond Chrome's security boundary. Google rates the issue High and has released a stable-channel fix in 157.0.8103.38; no public exploit code has been identified at time of analysis, and the issue carries an act_now priority with a 9.6 CVSS score reflecting the sandbox escape potential.

RemediationAI

Vendor-released patch: update Google Chrome to 157.0.8103.38 or later via the stable channel; the fix is documented in the stable-channel release notes at https://chromereleases.googleblog.com/2026/11/stable-channel-update-for-desktop.html. Confirm the installed build reaches 157.0.8103.38 or higher on every managed endpoint, and push the version through your browser management tooling rather than relying on user-initiated updates, since exploitation only requires the victim to open a crafted HTML page. The supplied sources describe no workaround or feature-level mitigation, so updating is the only complete fix identified; organizations that cannot immediately deploy 157.0.8103.38 have no vendor-documented compensating control to fall back on beyond limiting exposure to untrusted web content, and the Chromium issue at https://issues.chromium.org/issues/577400245 should be monitored for any additional guidance.

Affected VersionsENISA

Chrome 157.0.8103.38 <157.0.8103.38

Affected Packages

euvd chrome fix: 157.0.8103.38

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The flaw is classified as CWE-863 (Incorrect Authorization), meaning a security-sensitive operation in Chrome's FileSystem code path is reachable without the caller holding the privileges or permission state it should require. Chrome's FileSystem surface straddles the browser-process privilege boundary - content in a renderer interacts with file-system brokering handled at higher privilege - so a missing or wrong authorization check there is what turns a renderer-side compromise into code execution outside the sandbox, which is why the CVSS vector carries S:C (scope change) alongside C:H/I:H/A:H. The vector AV:N/AC:L/PR:N/UI:R indicates the attack is network-delivered, requires no credentials, has no special attack complexity beyond the victim opening attacker-supplied HTML, and depends on that user interaction; the supplied sources do not detail which FileSystem feature or configuration is abused, nor the exact authorization check that fails, so the trigger mechanism beyond the crafted HTML page should be treated as unverified. Authentication requirements are unauthenticated per PR:N in the assessed vector.

Know when the next one hits your stack

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (Chrome) PRIMARY 9.6 CRITICAL
AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
vuln.today AI 9.6 CRITICAL

Network-delivered crafted HTML with no auth (AV:N/PR:N) but requiring the victim to open it (UI:R); sandbox escape crosses the trust boundary (S:C) enabling full code execution (C:H/I:H/A:H).

3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Primary rating from Vendor (Chrome).

CVSS VectorVendor: Chrome

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

2
CVE Published
Nov 03, 2026 - 20:42 cve.org
CRITICAL 9.6
CVE Published
Nov 03, 2026 - 20:42 cve.org
UNKNOWN (no severity yet)

DescriptionCVE.org

Incorrect authorization in FileSystem in Google Chrome prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to potentially execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)

Executive ViewAI

Why It Matters

Google Chrome versions prior to 157.0.8103.38 contain a critical sandbox escape vulnerability (CVE-2026-121104) that allows remote, unauthenticated attackers to execute arbitrary code outside the browser's security boundary if a user is socially engineered into visiting a malicious webpage. This affects all desktop users and could lead to full system compromise, data theft, or malware installation, making it a priority for immediate remediation across the organization.

Business Impact: Severe
Compensating Controls

Apply vendor patch.

Threat Intelligence Overview

Prevalence
Ubiquitous
Google Chrome is among the most widely deployed desktop browsers worldwide
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV No
Public POC No
EPSS N/A
Patch available Yes
Active threat No
Deciding rule
CRITICAL severity
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision
Scheduled
Exploitation
None
System Exposure· derived
Open
Automatable
No
Human Impact
Very High
Technical Impact
Total

Priority Score

48
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +48
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy