Google Chrome up to 148.0.7778.179 Site Isolation improper isolation or compartmentalization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability was found in Google Chrome. It has been declared as critical. This impacts an unknown function of the component Site Isolation. The manipulation results in improper isolation or compartmentalization. This vulnerability is reported as CVE-2026-9903. The attack can be launched remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Google Chrome. Affected is some unknown processing of the component Site Isolation. The manipulation with an unknown input leads to a improper isolation or compartmentalization vulnerability. CWE is classifying the issue as CWE-653. The product does not properly compartmentalize or isolate functionality, processes, or resources that require different privilege levels, rights, or permissions. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Insufficient validation of untrusted input in Site Isolation in Google Chrome prior to 148.0.7778.216 allowed a remote attacker who had compromised the renderer process to bypass site isolation via a crafted MHTML page. (Chromium security severity: High)

The advisory is available at chromereleases.googleblog.com. This vulnerability is traded as CVE-2026-9903 since 05/28/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 05/30/2026).

Upgrading to version 148.0.7778.216 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1733). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Google Chrome
  • Microsoft Edge

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper isolation or compartmentalization
CWE: CWE-653
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Chrome 148.0.7778.216

Timelineinfo

05/28/2026 CVE reserved
05/29/2026 +1 days Advisory disclosed
05/29/2026 +0 days VulDB entry created
05/30/2026 +1 days VulDB entry last update

Sourcesinfo

Vendor: google.com
Product: google.com

Advisory: 498783
Status: Confirmed

CVE: CVE-2026-9903 (🔒)
GCVE (CVE): GCVE-0-2026-9903
GCVE (VulDB): GCVE-100-367002
CERT Bund: WID-SEC-2026-1733 - Google Chrome und Microsoft Edge: Mehrere Schwachstellen

Entryinfo

Created: 05/29/2026 08:46
Updated: 05/30/2026 03:13
Changes: 05/29/2026 08:46 (57), 05/30/2026 03:13 (7)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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