CVE-2019-20175
The guest system can crash the QEMU process in the host system via a special SCSI_IOCTL_SEND_COMMAND.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 3.36% probability · 89th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-754
- Affected
- qemu/qemu
- Source
- cve@mitre.org
EPSS 3.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg01651.htmlExploit, Mailing List, Third Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg03869.htmlMailing List, Third Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg00597.htmlThird Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg02165.htmlMailing List, Patch, Third Party Advisory
- https://www.mail-archive.com/qemu-devel%40nongnu.org/msg667396.html
- https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg01651.htmlExploit, Mailing List, Third Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg03869.htmlMailing List, Third Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg00597.htmlThird Party Advisory
- https://lists.nongnu.org/archive/html/qemu-devel/2019-11/msg02165.htmlMailing List, Patch, Third Party Advisory
- https://www.mail-archive.com/qemu-devel%40nongnu.org/msg667396.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.