CVE-2026-87491
Google Chromium V8 Out of Bounds Write Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 23 September 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
Out of bounds write in V8 in Google Chrome prior to 153.0.8010.36 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Medium)
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 0.86% probability · 56th percentile
- CISA KEV
- Listed 9 September 2026 · due 23 September 2026
- Weakness
- CWE-787
- Affected
- google/chrome
- Source
- chrome-cve-admin@google.com
CISA notes
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. https://chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop_0808145027.html ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-87491
References
- https://chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop_0808145027.htmlRelease Notes, Vendor Advisory
- https://issues.chromium.org/issues/543557673Permissions Required
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-87491US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.