Overview
- Description
- 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.
- Source
- cve@mitre.org
- NVD status
- Modified
Risk scores
CVSS 3.0
- Type
- Primary
- Base score
- 7
- Impact score
- 5.9
- Exploitability score
- 1
- Vector string
- CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Severity
- HIGH
CVSS 2.0
- Type
- Primary
- Base score
- 4.4
- Impact score
- 6.4
- Exploitability score
- 3.4
- Vector string
- AV:L/AC:M/Au:N/C:P/I:P/A:P
Weaknesses
- nvd@nist.gov
- CWE-863
Social media
- Hype score
- Not currently trending
Configurations
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