snapd 2.54.2 did not properly validate the location of the snap-confine binary. A local attacker who can hardlink this binary to another location to cause snap-confine to execute other arbitrary binaries and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1
Metrics
CVSS Version: 3.1 |
Base Score: 7.8 HIGH Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
l➤ Exploitability Metrics: Attack Vector (AV)* LOCAL Attack Complexity (AC)* HIGH Privileges Required (PR)* LOW User Interaction (UI)* NONE Scope (S)* CHANGED
l➤ Impact Metrics: Confidentiality Impact (C)* HIGH Integrity Impact (I)* HIGH Availability Impact (A)* HIGH
Weakness Enumeration (CWE)
CWE-ID: CWE-59 CWE Name: CWE-59 Improper Link Resolution Before File Access (
Link Following
) Source: Canonical Ltd.
Common Attack Pattern Enumeration and Classification (CAPEC)