Ubuntu 19.10 - ubuntu-aufs-modified mmap_region() Breaks Refcounting in overlayfs/shiftfs Error Path

Tested on 19.10. Ubuntu's aufs kernel patch includes the following change which I interestingly can't see in the AUFS code at https://github.com/sfjro/aufs5-linux/blob/master/mm/mmap.c: ================================================================== +define vmafputvma vmadofputvma, func, LINE...

Ubuntu shiftfs refcount Underflow / Type Confusion

Ubuntu: refcount underflow and type confusion in shiftfs Tested on Ubuntu 19.10, kernel "5.3.0-19-generic 20-Ubuntu". Ubuntu ships a filesystem "shiftfs" in fs/shiftfs.c in the kernel tree that doesn't exist upstream. This filesystem can be mounted from user namespaces, meaning that this is...

UBUNTU-CVE-2019-15793

In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, several locations which shift ids translate user/group ids before performing operations in the lower filesystem were translating them into inituserns, whereas they should have been translated in...

Ubuntu ubuntu-aufs-modified mmap_region() Refcounting Issue

Ubuntu: ubuntu-aufs-modified mmapregion breaks refcounting in overlayfs/shiftfs error path Tested on 19.10. Ubuntu's aufs kernel patch includes the following change which I interestingly can't see in the AUFS code at https://github.com/sfjro/aufs5-linux/blob/master/mm/mmap.c:...

The vulnerability of the map_write() function in “kernel/user_namespace.c” in the Linux operating system allows a hacker to gain access to confidential data, compromise its integrity, and cause service failures.

The vulnerability of the mapwrite function in “kernel/usernamespace.c” in the Linux operating system is related to improper authorization. Exploiting this vulnerability can allow an attacker to access confidential data, compromise its integrity, and cause service failures...

Linux - Nested User Namespace idmap Limit Local Privilege Escalation (Metasploit)

This module requires Metasploit: https://metasploit.com/download Current source: https://github.com/rapid7/metasploit-framework class MetasploitModule 'Linux Nested User Namespace idmap Limit Local Privilege Escalation', 'Description' = %q This module exploits a vulnerability in Linux kernels...

Linux Nested User Namespace idmap Limit Local Privilege Escalation Exploit

This Metasploit module exploits a vulnerability in Linux kernels 4.15.0 to 4.18.18, and 4.19.0 to 4.19.1, where broken uid/gid mappings between nested user namespaces and kernel uid/gid mappings allow elevation to root CVE-2018-18955. The target system must have unprivileged user namespaces enabl...

CVE-2018-18955

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, mapwrite in kernel/usernamespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAPSYSADMIN in an affected user namespace can bypass access controls on resources...

CVE-2018-18955

CVE-2018-18955 affects Linux kernels 4.15.x–4.19.x, with privilege escalation via map_write() in kernel/user_namespace.c when nested user namespaces have more than 5 UID/GID ranges. A user with CAP_SYS_ADMIN in the affected namespace can bypass controls outside the namespace (e.g., read /etc/shad...

EUVD-2018-10659

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, mapwrite in kernel/usernamespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAPSYSADMIN in an affected user namespace can bypass access controls on resources...

CVE-2018-18955

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, mapwrite in kernel/usernamespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAPSYSADMIN in an affected user namespace can bypass access controls on resources...

Linux - Broken uid/gid Mapping for Nested User Namespaces

commit 6397fac4915a "userns: bump idmap limits to 340" increases the number of possible uid/gid mappings that a namespace can have from 5 to 340. This is implemented by switching to a different data structure if the number of mappings exceeds 5: Instead of linear search over an unsorted array of...

Linux Nested User Namespace idmap Limit Local Privilege Escalation

This module exploits a vulnerability in Linux kernels 4.15.0 to 4.18.18, and 4.19.0 to 4.19.1, where broken uid/gid mappings between nested user namespaces and kernel uid/gid mappings allow elevation to root CVE-2018-18955. The target system must have unprivileged user namespaces enabled and the...

CVE-2018-6559

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...

CVE-2018-6559

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...

CVE-2018-6559

CVE-2018-6559 affects the Linux kernel overlayfs in Ubuntu 18.04/18.10. The vulnerability arises when mapping directory contents permissions inside nested user namespaces; a local attacker could exploit this to reveal names of files they would not normally access, bypassing some access controls. ...

CVE-2018-6559

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...

CVE-2018-6559

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...

CVE-2018-6559: Exposure of Sensitive Information to an Unauthorized Actor

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...

UBUNTU-CVE-2018-6559

The Linux kernel, as used in Ubuntu 18.04 LTS and Ubuntu 18.10, allows local users to obtain names of files in which they would not normally be able to access via an overlayfs mount inside of a user namespace...