What is the CVSS score of CVE-2026-17991?

CVE-2026-17991 has a contested CVSS base score of 9.6 from a third party (e.g. CISA-ADP), while the vendor rates it Critical. vuln.today uses the vendor rating as authoritative.

Which versions of Google Chrome are affected by CVE-2026-17991?

Google Chrome desktop (before version 151.0.7922.72) contains a critical sandbox escape vulnerability in its AI component that could enable system-level compromise if an attacker has previously…. A patch is available.

How to fix or mitigate CVE-2026-17991?

Within 24 hours, audit Chrome version deployment across your organization and establish a patch rollout schedule. Within 7 days, deploy Chrome version 151.0.7922.72 or later to a test environment and verify compatibility with critical business applications. Within 30 days, complete organization-wide rollout of the patched Chrome version to all endpoints, prioritizing systems with the highest user exposure and access to sensitive data.

Google Chrome CVE-2026-17991

EUVD-2026-50917 CRITICAL

Improper Input Validation (CWE-20)

2026-07-30 Chrome

GHSA-c4r5-cggq-5cfm

Information Disclosure Google

Critical

Disputed · 9.6 Vendor: Chrome

Severity by source

Sources disagree (Low–Critical)

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

8.3 HIGH

AC:H because exploitation requires first chaining a separate renderer compromise; UI:R since the victim must load a crafted page; S:C and full C/I/A reflect the sandbox escape to the browser process.

3.1 AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H

4.0 AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

SUSE

CRITICAL

qualitative

Red Hat

4.3 LOW

qualitative

vuln.today treats the vendor’s rating as authoritative. A higher third-party CVSS (e.g. CISA-ADP) is shown for transparency but does not drive the headline severity.

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

Analysis Generated

Jul 30, 2026 - 19:38 vuln.today

Patch available

Jul 30, 2026 - 02:02 EUVD

CVE Published

Jul 30, 2026 - 00:25 cve.org

UNKNOWN (no severity yet)

CVE Published

Jul 30, 2026 - 00:25 cve.org

CRITICAL 9.6

DescriptionCVE.org

Insufficient validation of untrusted input in AI in Google Chrome prior to 151.0.7922.72 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Low)

AnalysisAI

Sandbox escape in Google Chrome desktop before 151.0.7922.72 lets an attacker who has already compromised the renderer process break out to higher-privileged browser context via a crafted HTML page, rooted in insufficient validation of untrusted input in the AI component (CWE-20). NVD rates it CVSS 9.6 while Google labels the Chromium security severity 'Low', reflecting that renderer compromise is a hard prerequisite; there is no public exploit identified at time of analysis and EPSS is low at 0.17%. A vendor patch is available and CISA SSVC records exploitation as none.

Technical ContextAI

The flaw sits in Chrome's AI subsystem and is classified CWE-20 (Improper Input Validation), meaning data crossing a trust boundary is consumed without adequate checks. In Chromium's multi-process architecture the renderer runs untrusted web content inside a sandbox, and the privileged browser process is meant to be isolated from it; a sandbox escape defeats that boundary. The affected code path processes untrusted input reaching the AI feature from an already-hostile renderer, allowing that content to influence higher-privilege logic. The CPE cpe:2.3:a:google:chrome:*:*:*:*:*:*:*:* identifies all Chrome builds prior to 151.0.7922.72 on the desktop stable channel.

RemediationAI

Vendor-released patch: 151.0.7922.72 - upgrade Chrome to 151.0.7922.72 or later via the Stable Channel desktop update and restart the browser to apply it, as described at https://chromereleases.googleblog.com/2026/07/stable-channel-update-for-desktop_0887107924.html. Chrome auto-updates by default, so confirm the update actually installed (chrome://settings/help) across managed fleets rather than assuming it applied. Until patched, reduce exposure by ensuring users restart browsers promptly and, where the affected AI feature is governed by enterprise policy, disabling it removes the vulnerable code path at the cost of losing that functionality; because exploitation also requires a separate renderer compromise, keeping site isolation enabled and avoiding untrusted browsing meaningfully limits the practical attack surface.