CVE-2019-20175

Name	CVE-2019-20175
Description	DISPUTED An issue was discovered in ide_dma_cb() in hw/ide/core.c in QEMU 2.4.0 through 4.2.0. The guest system can crash the QEMU process in the host system via a special SCSI_IOCTL_SEND_COMMAND. It hits an assertion that implies that the size of successful DMA transfers there must be a multiple of 512 (the size of a sector). NOTE: a member of the QEMU security team disputes the significance of this issue because a "privileged guest user has many ways to cause similar DoS effect, without triggering this assert."
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
NVD severity	medium

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
qemu (PTS)	stretch	1:2.8+dfsg-6+deb9u9	vulnerable
	stretch (security)	1:2.8+dfsg-6+deb9u11	vulnerable
	buster	1:3.1+dfsg-8+deb10u7	vulnerable
	buster (security)	1:3.1+dfsg-8+deb10u8	vulnerable
	bullseye, sid	1:5.1+dfsg-4	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
qemu	source	(unstable)	(unfixed)	unimportant

Notes

https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg01651.html
https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg03869.html
https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg00597.html
https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg02165.html
Marked unimportant, as negligible security impact (a privileged guest
can trigger similar issues without triggering the specific assert) and
is disputed by QEMU security team.