CVE - CVE-2018-18955

CVE-ID
CVE-2018-18955	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
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.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
BID:105941 URL:http://www.securityfocus.com/bid/105941 CONFIRM:https://security.netapp.com/advisory/ntap-20190416-0003/ CONFIRM:https://support.f5.com/csp/article/K39103040 EXPLOIT-DB:45886 URL:https://www.exploit-db.com/exploits/45886/ EXPLOIT-DB:45915 URL:https://www.exploit-db.com/exploits/45915/ MISC:http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d2f007dbe7e4c9583eea6eb04d60001e85c6f1bd MISC:https://bugs.chromium.org/p/project-zero/issues/detail?id=1712 MISC:https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.19 MISC:https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.2 MISC:https://github.com/torvalds/linux/commit/d2f007dbe7e4c9583eea6eb04d60001e85c6f1bd UBUNTU:USN-3832-1 URL:https://usn.ubuntu.com/3832-1/ UBUNTU:USN-3833-1 URL:https://usn.ubuntu.com/3833-1/ UBUNTU:USN-3835-1 URL:https://usn.ubuntu.com/3835-1/ UBUNTU:USN-3836-1 URL:https://usn.ubuntu.com/3836-1/ UBUNTU:USN-3836-2 URL:https://usn.ubuntu.com/3836-2/
Assigning CNA
MITRE Corporation
Date Record Created
20181105	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20181105)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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