CVE - CVE-2019-18420

CVE-ID
CVE-2019-18420	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOP_initialise hypercall. hypercall_create_continuation() is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format character was done using BUG(), which crashes Xen. One path, via the VCPUOP_initialise hypercall, has a bad format character. The BUG() can be hit if VCPUOP_initialise executes for a sufficiently long period of time for a continuation to be created. Malicious guests may cause a hypervisor crash, resulting in a Denial of Service (DoS). Xen versions 4.6 and newer are vulnerable. Xen versions 4.5 and earlier are not vulnerable. Only x86 PV guests can exploit the vulnerability. HVM and PVH guests, and guests on ARM systems, cannot exploit the vulnerability.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
BUGTRAQ:20200114 [SECURITY] [DSA 4602-1] xen security update URL:https://seclists.org/bugtraq/2020/Jan/21 DEBIAN:DSA-4602 URL:https://www.debian.org/security/2020/dsa-4602 FEDORA:FEDORA-2019-376ec5c107 URL:https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I5WWPW4BSZDDW7VHU427XTVXV7ROOFFW/ FEDORA:FEDORA-2019-865bb16900 URL:https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2BQKX7M2RHCWDBKNPX4KEBI3MJIH6AYZ/ FEDORA:FEDORA-2019-cbb732f760 URL:https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IZYATWNUGHRBG6I3TC24YHP5Y3J7I6KH/ GENTOO:GLSA-202003-56 URL:https://security.gentoo.org/glsa/202003-56 MISC:http://xenbits.xen.org/xsa/advisory-296.html MLIST:[oss-security] 20191031 Xen Security Advisory 296 v4 (CVE-2019-18420) - VCPUOP_initialise DoS URL:http://www.openwall.com/lists/oss-security/2019/10/31/1 SUSE:openSUSE-SU-2019:2506 URL:http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00037.html
Assigning CNA
MITRE Corporation
Date Record Created
20191024	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20191024)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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