Upstream information
Description
An issue was discovered in Xen XAPI before 2020-12-15. Certain xenstore keys provide feedback from the guest, and are therefore watched by toolstack. Specifically, keys are watched by xenopsd, and data are forwarded via RPC through message-switch to xapi. The watching logic in xenopsd sends one RPC update containing all data, any time any single xenstore key is updated, and therefore has O(N^2) time complexity. Furthermore, message-switch retains recent (currently 128) RPC messages for diagnostic purposes, yielding O(M*N) space complexity. The quantity of memory a single guest can monopolise is bounded by xenstored quota, but the quota is fairly large. It is believed to be in excess of 1G per malicious guest. In practice, this manifests as a host denial of service, either through message-switch thrashing against swap, or OOMing entirely, depending on dom0's configuration. (There are no quotas in xenopsd to limit the quantity of keys that result in RPC traffic.) A buggy or malicious guest can cause unreasonable memory usage in dom0, resulting in a host denial of service. All versions of XAPI are vulnerable. Systems that are not using the XAPI toolstack are not vulnerable.SUSE information
Overall state of this security issue: Does not affect SUSE products
This issue is currently rated as having moderate severity.
| National Vulnerability Database | |
|---|---|
| Base Score | 7.8 |
| Vector | AV:N/AC:L/Au:N/C:N/I:N/A:C |
| Access Vector | Network |
| Access Complexity | Low |
| Authentication | None |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | Complete |
| National Vulnerability Database | SUSE | |
|---|---|---|
| Base Score | 7.5 | 6.5 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
| Attack Vector | Network | Local |
| Attack Complexity | Low | Low |
| Privileges Required | None | Low |
| User Interaction | None | None |
| Scope | Unchanged | Changed |
| Confidentiality Impact | None | None |
| Integrity Impact | None | None |
| Availability Impact | High | High |
| CVSSv3 Version | 3.1 | 3.1 |
Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Micro 5.1 | xen | Not affected |
| SUSE Linux Enterprise Micro 5.2 | xen | Not affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise High Performance Computing 12 SP5 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | xen | Analysis |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | xen | Analysis |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | xen | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP5 | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | xen | Analysis |
| SUSE Linux Enterprise Server 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 15-ESPOS | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP5 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | xen | Not affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| HPE Helion OpenStack 8 | xen | Not affected |
| SUSE CaaS Platform 3.0 | xen | Not affected |
| SUSE CaaS Platform 4.0 | xen | Not affected |
| SUSE Enterprise Storage 5 | xen | Not affected |
| SUSE Enterprise Storage 6 | xen | Not affected |
| SUSE Enterprise Storage 7 | xen | Not affected |
| SUSE Enterprise Storage 7.1 | xen | Not affected |
| SUSE Linux Enterprise Desktop 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Desktop 11 SP4 | xen | Not affected |
| SUSE Linux Enterprise Desktop 12 SP2 | xen | Not affected |
| SUSE Linux Enterprise Desktop 12 SP3 | xen | Not affected |
| SUSE Linux Enterprise Desktop 12 SP4 | xen | Not affected |
| SUSE Linux Enterprise Desktop 15 | xen | Not affected |
| SUSE Linux Enterprise Desktop 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise Desktop 15 SP2 | xen | Not affected |
| SUSE Linux Enterprise Desktop 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15-ESPOS | xen | Not affected |
| SUSE Linux Enterprise High Performance Computing 15-LTSS | xen | Not affected |
| SUSE Linux Enterprise Micro 5.0 | xen | Unsupported |
| SUSE Linux Enterprise Module for Basesystem 15 | xen | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise Module for Server Applications 15 | xen | Not affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise Point of Sale 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | xen | Not affected |
| SUSE Linux Enterprise Point of Service 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Point of Service Image Server 12 SP2 | xen | Not affected |
| SUSE Linux Enterprise Real Time 15 SP2 | xen | Analysis |
| SUSE Linux Enterprise Real Time 15 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server 11 SP3-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 11 SP4 | xen | Not affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 11 SP4-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP2 | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP2-BCL | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP2-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP3-BCL | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP3-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP4 | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | xen | Not affected |
| SUSE Linux Enterprise Server 12 SP4-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 15 | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | xen | Analysis |
| SUSE Linux Enterprise Server 15 SP3-BCL | xen | Not affected |
| SUSE Linux Enterprise Server 15-LTSS | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 11 SP4 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 | xen | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 11 SP3 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 11 SP4 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP2 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP3 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP4 | xen | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP5 | xen | Not affected |
| SUSE Manager Proxy 4.0 | xen | Not affected |
| SUSE Manager Proxy 4.1 | xen | Not affected |
| SUSE Manager Proxy 4.2 | xen | Not affected |
| SUSE Manager Retail Branch Server 4.0 | xen | Not affected |
| SUSE Manager Retail Branch Server 4.1 | xen | Not affected |
| SUSE Manager Retail Branch Server 4.2 | xen | Not affected |
| SUSE Manager Server 4.0 | xen | Not affected |
| SUSE Manager Server 4.1 | xen | Not affected |
| SUSE Manager Server 4.2 | xen | Not affected |
| SUSE OpenStack Cloud 7 | xen | Not affected |
| SUSE OpenStack Cloud 8 | xen | Not affected |
| SUSE OpenStack Cloud 9 | xen | Not affected |
| SUSE OpenStack Cloud Crowbar 8 | xen | Not affected |
| SUSE OpenStack Cloud Crowbar 9 | xen | Not affected |
| openSUSE Leap 15.3 | xen | Not affected |
| openSUSE Leap Micro 5.2 | xen | Not affected |
| Products at an unknown state of their lifecycle. | ||
| SUSE Linux Enterprise Server LTSS Extended Security 12-SP5 | xen | Not affected |
SUSE Timeline for this CVE
CVE page created: Wed Dec 2 10:48:06 2020CVE page last modified: Tue Nov 12 19:28:25 2024