Inappropriate implementation in Extensions in Google Chrome prior to 140.0.7339.80 allowed a remote attacker to bypass content security policy via a… (CVE-2025-9866)
A vulnerability in Google Chrome Extensions prior to version 140.0.7339.80 allows a remote attacker to bypass the content security policy by using a crafted HTML page. This flaw has a high severity rating with a CVSS score of 8.8, indicating significant potential impact on confidentiality, integrity, and availability.
AI Analysis
Technical Summary
CVE-2025-9866 describes an inappropriate implementation in the Extensions component of Google Chrome versions before 140.0.7339.80. This vulnerability enables a remote attacker to bypass the browser's content security policy (CSP) by delivering a specially crafted HTML page. The CSP bypass can lead to unauthorized script execution or data exposure within the browser context. The CVSS 3.1 vector indicates the attack requires no privileges and low attack complexity but requires user interaction. The impact includes high confidentiality, integrity, and availability consequences.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to bypass the content security policy in affected Chrome versions, potentially leading to unauthorized script execution, data theft, or other malicious actions within the browser environment. The high CVSS score reflects the critical nature of these impacts.
Mitigation Recommendations
A fix is available in Google Chrome version 140.0.7339.80. Users and administrators should update to this version or later to remediate the vulnerability. No additional mitigation steps are indicated in the provided data.
Inappropriate implementation in Extensions in Google Chrome prior to 140.0.7339.80 allowed a remote attacker to bypass content security policy via a… (CVE-2025-9866)
Description
A vulnerability in Google Chrome Extensions prior to version 140.0.7339.80 allows a remote attacker to bypass the content security policy by using a crafted HTML page. This flaw has a high severity rating with a CVSS score of 8.8, indicating significant potential impact on confidentiality, integrity, and availability.
CVSS v3.1
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-9866 describes an inappropriate implementation in the Extensions component of Google Chrome versions before 140.0.7339.80. This vulnerability enables a remote attacker to bypass the browser's content security policy (CSP) by delivering a specially crafted HTML page. The CSP bypass can lead to unauthorized script execution or data exposure within the browser context. The CVSS 3.1 vector indicates the attack requires no privileges and low attack complexity but requires user interaction. The impact includes high confidentiality, integrity, and availability consequences.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to bypass the content security policy in affected Chrome versions, potentially leading to unauthorized script execution, data theft, or other malicious actions within the browser environment. The high CVSS score reflects the critical nature of these impacts.
Mitigation Recommendations
A fix is available in Google Chrome version 140.0.7339.80. Users and administrators should update to this version or later to remediate the vulnerability. No additional mitigation steps are indicated in the provided data.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-5g75-w57p-pj3x
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2025-9866"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ab74f35f7a7c54106e138d2
Added to database: 09/26/2026, 04:51:01 UTC
Last enriched: 09/26/2026, 04:59:03 UTC
Last updated: 09/27/2026, 01:47:40 UTC
Views: 17
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