CVE-2015-8660

Published: 28 December 2015

The ovl_setattr function in fs/overlayfs/inode.c in the Linux kernel through 4.3.3 attempts to merge distinct setattr operations, which allows local users to bypass intended access restrictions and modify the attributes of arbitrary overlay files via a crafted application.

From the Ubuntu Security Team

Nathan Williams discovered that overlayfs in the Linux kernel incorrectly handled setattr operations. A local unprivileged attacker could use this to create files with administrative permission attributes and execute arbitrary code with elevated privileges.

Notes

android kernels (flo, goldfish, grouper, maguro, mako and manta) are
not supported on the Ubuntu Touch 14.10 and earlier preview kernels
linux-lts-saucy no longer receives official support
linux-lts-quantal no longer receives official support

kernel 3.16 and older not affected

Status

Severity score breakdown

References

• http://www.openwall.com/lists/oss-security/2015/12/23/5
• https://ubuntu.com/security/notices/USN-2858-1
• https://ubuntu.com/security/notices/USN-2858-2
• https://ubuntu.com/security/notices/USN-2858-3
• https://ubuntu.com/security/notices/USN-2857-2
• https://ubuntu.com/security/notices/USN-2857-1
• https://www.cve.org/CVERecord?id=CVE-2015-8660
• NVD
• Launchpad
• Debian

Bugs

• https://bugzilla.redhat.com/show_bug.cgi?id=1291329
• https://launchpad.net/bugs/1528904