CVE-2026-8933

Published Jul 21, 2026

Last updated 9 hours ago

CVSS high 7.8
Ubuntu

Overview

Description
A local privilege escalation vulnerability exists in snap-confine, a set-capabilities core component used internally by Canonical snapd to construct the secure execution environment for snap applications. This vulnerability uniquely affects versions of snap-confine configured with set-capabilities (rather than standard set-uid-root installations). Due to a flaw in how privilege boundaries or security sandboxes are initialized when the binary runs under limited ambient capabilities, a local, unprivileged attacker can exploit this behavior to bypass intended restrictions and execute arbitrary code. Successful exploitation allows the local user to elevate their privileges to full root authority.
Source
security@ubuntu.com
NVD status
Awaiting Analysis

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

security@ubuntu.com
CWE-250

Social media

Hype score
Not currently trending

  1. 🔒💥 ¡ALERTA DE SEGURIDAD EN UBUNTU! Canonical revela 3 vulnerabilidades críticas en snapd que afectan versiones desde Ubuntu 16.04 LTS. CVE-2026-8933 permite escalado de privilegios. CVE-2026-15226 posibilita escape de confinación. CVE-2024-5300 expone contraseñas

    @DiarioBitcoin

    23 Jul 2026

    692 Impressions

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  2. 🚨 High-Severity Ubuntu Alert Qualys TRU has disclosed CVE-2026-8933, a local privilege escalation in snap-confine that grants full root access to any unprivileged local user on default Ubuntu Desktop installations. The flaw arises from race conditions in temporary directory h

    @FriendOfTheInst

    22 Jul 2026

    99 Impressions

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References

Sources include official advisories and independent security research.