| Name | CVE-2019-20175 |
| Description | 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, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| qemu (PTS) | jessie, jessie (lts) | 1:2.1+dfsg-12+deb8u23 | vulnerable |
| stretch (security) | 1:2.8+dfsg-6+deb9u17 | vulnerable |
| stretch (lts), stretch | 1:2.8+dfsg-6+deb9u19 | vulnerable |
| buster | 1:3.1+dfsg-8+deb10u8 | vulnerable |
| buster (security) | 1:3.1+dfsg-8+deb10u12 | vulnerable |
| bullseye | 1:5.2+dfsg-11+deb11u3 | fixed |
| bullseye (security) | 1:5.2+dfsg-11+deb11u2 | fixed |
| bookworm | 1:7.2+dfsg-7+deb12u5 | fixed |
| trixie | 1:8.2.1+ds-2 | fixed |
| sid | 1:8.2.3+ds-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| qemu | source | (unstable) | 1:5.0-1 | 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.
Fixed by: https://gitlab.com/qemu-project/qemu/-/commit/ed78352a59ea7acf7520d4d47a96b9911bae7fc3 (v5.0.0-rc0)