Vulnerability in Xen
CVE-2020-11743
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 for success, and a negative number for errors. Some misplaced brackets cause one error path to return 1 instead of a negative value. The grant table code in Linux treats this condition as success, and proceeds with incorrectly initialised state. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to map a grant, it hits the incorrect error path. This will crash a Linux based dom0 or backend domain.
EPSS: 0.005 (41.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Xen — versions 4.13.0
- Fedoraproject Fedora — versions 32
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Exploit, x_refsource_MISC, Vendor Advisory)
- cve@mitre.org (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- cve@mitre.org (mailing-list, x_refsource_MLIST, Patch, Third Party Advisory)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (vendor-advisory, x_refsource_SUSE)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (vendor-advisory, x_refsource_GENTOO)
- cve@mitre.org (vendor-advisory, x_refsource_DEBIAN)
Frequently asked questions
- What is CVE-2020-11743?
- CVE-2020-11743 is a medium-severity vulnerability in Xen, classified under Improper Handling of Exceptional Conditions. CVSS score: 5.5/10. Published 2020-04-14.
- How severe is CVE-2020-11743?
- Medium severity. CVSS v3 base score is 5.5 out of 10.