A flaw was found in qemu Media Transfer Protocol (MTP). The code opening files in usb_mtp_get_object and usb_mtp_get_partial_object and directories in usb_mtp_object_readdir doesn't consider that the underlying filesystem may have changed since the time lstat(2) was called in usb_mtp_object_alloc, a classical TOCTTOU problem. An attacker with write access to the host filesystem shared with a guest can use this property to navigate the host filesystem in the context of the QEMU process and read any file the QEMU process has access to. Access to the filesystem may be local or via a network share protocol such as CIFS.
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state.
| Link | Tags |
|---|---|
| https://lists.debian.org/debian-lts-announce/2019/02/msg00041.html | third party advisory mailing list |
| http://www.securityfocus.com/bid/106212 | third party advisory vdb entry |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CGCFIFSIWUREEQQOZDZFBYKWZHXCWBZN/ | third party advisory vendor advisory |
| https://usn.ubuntu.com/3923-1/ | third party advisory vendor advisory |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KJMTVGDLA654HNCDGLCUEIP36SNJEKK7/ | third party advisory vendor advisory |
| http://lists.opensuse.org/opensuse-security-announce/2019-03/msg00042.html | vendor advisory mailing list third party advisory |
| https://www.debian.org/security/2019/dsa-4454 | third party advisory vendor advisory |
| https://seclists.org/bugtraq/2019/May/76 | third party advisory mailing list |
| https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16872 | patch third party advisory issue tracking |