icon

We found results for “

CVE-2018-18955

Date: November 16, 2018

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction.

Language: C

Severity Score

Severity Score

Weakness Type (CWE)

Input Validation

CWE-20

Incorrect Authorization

CWE-863

CVSS v3.1

Base Score:
Attack Vector (AV): LOCAL
Attack Complexity (AC): HIGH
Privileges Required (PR): LOW
User Interaction (UI): NONE
Scope (S): UNCHANGED
Confidentiality (C): HIGH
Integrity (I): HIGH
Availability (A): HIGH

CVSS v2

Base Score:
Access Vector (AV): LOCAL
Access Complexity (AC): MEDIUM
Authentication (AU): NONE
Confidentiality (C): PARTIAL
Integrity (I): PARTIAL
Availability (A): PARTIAL
Additional information:

Do you need more information?

Contact Us