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CVE-2026-8559 Google CVE debrief

CVE-2026-8559 is a high-severity integer overflow vulnerability in Google Chrome's Internationalization component on Windows, disclosed by Google on May 14, 2026. The flaw allows remote attackers to perform out-of-bounds memory writes via crafted HTML pages, potentially enabling code execution or browser compromise. Google rated this Chromium security severity as High, though NVD-assigned CVSS 3.1 scoring indicates Medium severity (4.3) with network attack vector, low attack complexity, and required user interaction. The vulnerability affects all Chrome versions prior to 148.0.7778.168 on Windows platforms. Google addressed this in the Stable channel update released May 12, 2026. No known exploitation in the wild has been reported, and the vulnerability is not listed in CISA KEV. Organizations should prioritize updating Chrome installations on Windows endpoints to version 148.0.7778.168 or later.

Vendor
Google
Product
Chrome
CVSS
MEDIUM 4.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-14
Original CVE updated
2026-05-19
Advisory published
2026-05-14
Advisory updated
2026-05-19

Who should care

Organizations with Windows endpoints running Google Chrome; security teams managing browser update compliance; developers building web applications with internationalization features

Technical summary

An integer overflow in Chrome's Internationalization (i18n) component on Windows platforms allows out-of-bounds memory writes when processing specially crafted HTML content. The vulnerability stems from insufficient bounds checking during internationalization operations, enabling attackers to corrupt memory and potentially achieve arbitrary code execution within the browser sandbox. The attack requires user interaction (visiting a malicious page) but can be triggered remotely. Google patched this in Chrome 148.0.7778.168.

Defensive priority

high

Recommended defensive actions

  • Update Google Chrome on Windows systems to version 148.0.7778.168 or later
  • Verify Chrome auto-update is enabled for managed endpoints
  • Review browser version inventory for Windows devices running Chrome versions below 148.0.7778.168
  • Monitor for unexpected Chrome crashes or memory-related errors that may indicate exploitation attempts
  • Apply principle of least privilege for browser processes where feasible

Evidence notes

Vulnerability description and affected versions confirmed via NVD CPE data and Google Chrome Release blog. CVSS vector and severity ratings sourced from NVD. Chromium security severity rating of High per vendor advisory. Fix version 148.0.7778.168 confirmed in Chrome Stable channel release notes.

Official resources

2026-05-14