CVE-2026-70351: Microsoft WebP Image Extension Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Unlikely

Patch Tuesday

2026-Sep

Released

2026-09-08

Description

Integer overflow or wraparound in Microsoft WebP Image Extension allows an unauthorized attacker to execute code over a network.

FAQ

According to the CVSS metric, the attack vector is network (AV:N) and user interaction is required (UI:R). What is the target context of the remote code execution? This attack requires a user to open a specially crafted file from the attacker to initiate remote code execution.

Affected Products (1)

Windows

• WebP Image Extension

Security Updates (1)

• Release Note

Acknowledgments

Anonymous

Revision History

• 2026-09-08: Information published.