Allocation of Resources Without Limits or Throttling in Xen - CVE-2020-29570
Published: December 15, 2020 / Updated: December 23, 2020
Vulnerability identifier: #VU49139
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2020-29570
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
An issue was discovered in Xen through 4.14.x. Recording of the per-vCPU control block mapping maintained by Xen and that of pointers into the control block is reversed. The consumer assumes, seeing the former initialized, that the latter are also ready for use. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system.
Affected software
Xen
Debian Linux
Fedora
xen (Alpine package)
xen (Debian package)
xen
IBM Systems Director
Debian Linux
Fedora
xen (Alpine package)
xen (Debian package)
xen
IBM Systems Director
How to mitigate CVE-2020-29570
Install update from vendor's website.
xen (Alpine package) - update to 4.14.1-r0
xen (Debian package) - update to 4.11.4+57-g41a822c392-2
xen - addressed in versions 4.13.2-5.fc32, 4.14.0-14.fc33
xen (Debian package) - update to 4.11.4+57-g41a822c392-2
xen - addressed in versions 4.13.2-5.fc32, 4.14.0-14.fc33