Google Chrome: Improper access control in V8 allows origin policy bypass
Summary
Improper access control in the V8 JavaScript engine of Google Chrome allows a remote attacker to potentially bypass the web origin policy. The attacker needs a victim to open a crafted HTML page, and no authentication is required. A successful bypass could expose data across websites, for example in SaaS sessions or internal web applications used in the browser.
Affected
- Google Chrome prior to 156.0.8078.47
- Microsoft Edge prior to 156.0.4314.42 (Chromium-based)
- Linux: Chromium snap or distribution package (the Ubuntu chromium-browser package is marked not affected because it installs the Chromium snap)
Fixed in
- Google Chrome 156.0.8078.47 or later (Linux 156.0.8078.47; Windows and Mac 156.0.8078.47/.48 according to secondary reporting)
- A later Stable build (156.0.8078.79/.80 on Windows and Mac, 156.0.8078.79 on Linux, according to secondary reporting) is recommended
- Microsoft Edge 156.0.4314.42 or later
Workaround
Unknown. Updating is the recommended remedy.
Exploitation
- Exploitation in the wild: not stated by Google; not listed in CISA KEV.
- CISA SSVC: exploitation 'poc', not automatable, total technical impact.
- Public proof of concept: none found in research (this does not rule one out).
- EPSS: 0.25% (third-party figure, not verified).
Our recommendation
- Confirm that all Chrome and Edge installations are at least 156.0.8078.47 (Edge 156.0.4314.42 or later), and preferably the latest Stable build.
- Check that managed browsers receive updates via MDM or policy tooling.
- On Linux, verify that the Chromium snap or distribution package is updated.
- Monitor the Chromium issue tracker and CISA KEV for changes in exploitation status.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Chrome Releases: Stable Channel Update for Desktop chromereleases.googleblog.com
- Chromium issue tracker issues.chromium.org
- NVD record via Vulners vulners.com
- Ubuntu CVE tracker ubuntu.com
- HKCERT security bulletin (Microsoft Edge) www.hkcert.org
- ChromeGeek: Chrome 156 stable what's new www.chromegeek.com
- ChromeGeek: Chrome 156 security update fixes www.chromegeek.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 14:54.
Original description (NVD)
Improper access control in V8 in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to potentially bypass web origin policy via a crafted HTML page. (Chromium security severity: Medium)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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