CVE intelligence

CVE-2026-87766

Vulnerability intelligence

Published Sep 9, 2026Sources checked Oct 30, 2026

8.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-87766 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 19, 2026

See the Microsoft Security Update Guide for the update that applies to your product.

Vendor-listed releases

0.12.0-1

Ubuntu Security Notices guidance

Vendor revision: Sep 17, 2026

USN-8779-1 fixed vulnerabilities in Bubblewrap.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-87766?

A flaw was found in bubblewrap. During sandbox setup, creating files or directories under the new root can follow a parent symlink onto the host via /oldroot, writing attacker-chosen paths outside the sandbox as the launching user.

This happens before the sandboxed process starts. This issue is GHSA-pxhw-h44j-8pfx.

It is fixed in bubblewrap 0.12.0.

Source: NVD