CVE-2018-18955
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...
- Published
- Nov 16, 2018
- Updated
- Aug 5, 2024
- Assigning CNA
- mitre
- Evidence observed
- Nov 16, 2018
Primary CVSS
nvd · CVSS 3.0
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HModerate · next 30 days
- Percentile
- 97.0%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
Summary
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.
Sources
9- kernel-exploitsExploit
Various kernel exploits
- linux-kernel-exploitsExploit
linux-kernel-exploits Linux平台提权漏洞集合
Proof-of-concept exploit for CVE-2018-18955, a Linux kernel local privilege escalation vulnerability. Provides a working exploit to demonstrate the flaw.
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