CVE Watch21 sept 2026

CVE-2026-87491

Google Chromium V8 Out of Bounds Write Vulnerability

CVSS

8.8

Alto

EPSS

3.1%

p88

KEV

SÍ

9 sept 2026

Exploit Today

0-100

Publicado: 9 sept 2026 · Última mod.: 21 sept 2026 · CWE-787

EPSS · 30d

3.1%EPSS · 30 días3.1%

2026-09-252026-10-23

Ficha del catálogo KEV

Producto

Google / Chromium V8

Vulnerabilidad

Google Chromium V8 Out of Bounds Write Vulnerability

Añadido a KEV

9 sept 2026

Remediar antes de

23 sept 2026

Uso conocido en ransomware

Descripción resumida

Google Chromium V8 contains an out of bounds write vulnerability that allows a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. This vulnerability could affect multiple web browsers that utilize Chromium, including, but not limited to, Google Chrome, Microsoft Edge, and Opera.

Acción requerida

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.

Notas

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

Descripción técnica

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)

Referencias oficiales

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