Xen up to 4.9.x Hypervisor resource consumption

CVSS Meta Temp Score
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CTI Interest Score
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5.6$0-$5k0.00

A vulnerability, which was classified as problematic, was found in Xen up to 4.9.x (Virtualization Software). This affects an unknown part of the component Hypervisor. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. The summary by CVE is:

An issue was discovered in Xen through 4.9.x allowing x86 PV guest OS users to cause a denial of service (unbounded recursion, stack consumption, and hypervisor crash) or possibly gain privileges via crafted page-table stacking.

The bug was discovered 10/12/2017. The weakness was published 10/18/2017 by Security Team (Paul) as XSA-240 as confirmed security advisory (Website). The advisory is shared at xenbits.xen.org. This vulnerability is uniquely identified as CVE-2017-15595 since 10/18/2017. The exploitability is told to be easy. An attack has to be approached locally. No form of authentication is needed for exploitation. Technical details are unknown but a public exploit is available.

The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 6 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 103927 (Citrix XenServer Multiple Vulnerabilities (CTX228867)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Misc. and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176562 (Debian Security Update for xen (DSA 4369-1)).

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (103927) and Exploit-DB (43014). Similar entries are available at 107978, 107979, 107980 and 107982.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.1

VulDB Base Score: 3.8
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 103927
Nessus Name: Citrix XenServer Multiple Vulnerabilities (CTX228867)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 850584
OpenVAS Name: SuSE Update for xen openSUSE-SU-2017:2821-1 (xen)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

10/12/2017 🔍
10/18/2017 +6 days 🔍
10/18/2017 +0 days 🔍
10/18/2017 +0 days 🔍
10/18/2017 +0 days 🔍
10/18/2017 +0 days 🔍
10/18/2017 +0 days 🔍
12/07/2018 +415 days 🔍
01/17/2021 +772 days 🔍

Sourcesinfo

Advisory: XSA-240
Researcher: Security Team (Paul)
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-15595 (🔍)
OVAL: 🔍

SecurityFocus: 106182 - Xen Multiple Privilege Escalation and Denial of Service Vulnerabilities

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 10/19/2017 00:23
Updated: 01/17/2021 10:29
Changes: 10/19/2017 00:23 (63), 11/26/2019 07:00 (15), 01/17/2021 10:29 (12)
Complete: 🔍

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