CVE-2026-78954Network attack vector

Web origin bypass via extension authorization failure

Published Aug 25, 2026 · Updated Aug 25, 2026

Incorrect authorization in Google Chrome Extensions before 152.0.7977.65 allows remote attackers to bypass the web origin policy. Google has not published which Extensions authorization decision improperly accepts renderer-controlled input. Exploitation requires a crafted HTML page and an already compromised renderer process; the bypass crosses web-origin boundaries, while the exact accessible data or actions remain undisclosed.

CVSS severityUnavailable
Unscored
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect authorization in Google Chrome Extensions before 152.0.7977.65 allows remote attackers to bypass the web origin policy. Google has not published which Extensions authorization decision improperly accepts renderer-controlled input. Exploitation requires a crafted HTML page and an already compromised renderer process; the bypass crosses web-origin boundaries, while the exact accessible data or actions remain undisclosed.

The record

CVE
CVE-2026-78954
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
Google Cloud
Product
Google Chrome
Classifications
CWE-863, T1211
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=152.0.7977.65 <152.0.7977.65

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

Google Cloud · Google Chromeversion=152.0.7977.65 <152.0.7977.65

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1211Exploitation for Defense Evasion

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo