CVE-2020-35506

Description

A use-after-free vulnerability was found in the am53c974 SCSI host bus adapter emulation of QEMU in versions before 6.0.0 during the handling of the 'Information Transfer' command (CMD_TI). This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service or potential code execution with the privileges of the QEMU process.

CVSS Metrics

• v3.1•MEDIUM•Score: 6.7CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
• v2.0•MEDIUM•Score: 4.6AV:L/AC:L/Au:N/C:P/I:P/A:P

EPSS Trends

Current EPSS score: 0.03%• Percentile: 9%

Techniques & Countermeasures

• CWE-416•Use After Free

  The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected Systems

• qemu•qemu

  < 6.0.0

References (5)

• http://www.openwall.com/lists/oss-security/2021/04/16/3
• https://www.openwall.com/lists/oss-security/2021/04/16/3
• https://bugzilla.redhat.com/show_bug.cgi?id=1909996
• https://security.netapp.com/advisory/ntap-20210713-0006/
• https://security.gentoo.org/glsa/202208-27