Multiple vulnerabilities in Xen

Published: 2017-10-12 | Updated: 2017-11-29

Risk	Medium
Patch available	YES
Number of vulnerabilities	7
CVE-ID	CVE-2017-15588 CVE-2017-15589 CVE-2017-15590 CVE-2017-15592 CVE-2017-15593 CVE-2017-15594 CVE-2017-15595
CWE-ID	CWE-362 CWE-401 CWE-284 CWE-264 CWE-400
Exploitation vector	Local network
Public exploit	N/A
Vulnerable software Subscribe	Xen Server applications / Virtualization software
Vendor	Xen Project

Security Bulletin

This security bulletin contains information about 7 vulnerabilities.

1) Race condition

EUVDB-ID: #VU9446

Risk: Low

CVSSv3.1: 8.3 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15588

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to gain elevated privileges on the target system.

The weakness exists due to page type release race. An adjacent attacker can supply a stale TLB entry, trigger race condition and execute arbitrary code with elevated privileges.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-241.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Memory leak

EUVDB-ID: #VU9447

Risk: Low

CVSSv3.1: 3.8 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15589

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to obtain potentially sensitive information on the target system.

The weakness exists due to hypervisor stack leak in x86 I/O intercept code. An adjacent attacker can write data from uninitialized hypervisor stack memory and read arbitrary information.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-239.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Improper access control

EUVDB-ID: #VU9448

Risk: Low

CVSSv3.1: 5.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15590

CWE-ID: CWE-284 - Improper Access Control

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to cause DoS conditions on the target system.

The weakness exists due to an error with the setup of PCI MSI interrupts. An adjacent attacker can supply MSI and cause the hypervisor to crash.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-237.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Privilege escalation

EUVDB-ID: #VU9449

Risk: Low

CVSSv3.1: 6.6 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15592

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to cause DoS conditions or gain elevated privileges on the target system.

The weakness exists due to mishandling of self-linear shadow mappings for translated guests. An adjacent attacker can supply self-linear shadow mappings and cause the hypervisor to crash or possibly gain elevated privileges.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-243.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Memory leak

EUVDB-ID: #VU9450

Risk: Low

CVSSv3.1: 5.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15593

CWE-ID: CWE-401 - Missing release of memory after effective lifetime

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to cause DoS conditions on the target system.

The weakness exists due to mishandling of reference counts. An adjacent attacker can trigger memory leak and cause the service to crash.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-242.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

6) Privilege escalation

EUVDB-ID: #VU9451

Risk: Low

CVSSv3.1: 4.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15594

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to gain elevated privileges or cause DoS conditions on the target system.

The weakness exists due to mishandling of IDT settings during CPU hotplugging. An adjacent attacker can gain elevated privileges or cause hypervisor crash.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-244.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

7) Resource exhaustion

EUVDB-ID: #VU9452

Risk: Low

CVSSv3.1: 4.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-15595

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to gain elevated privileges or cause DoS conditions on the target system.

The weakness exists due to improper input validation. An adjacent attacker can supply specially crafted page-table stacking, trigger unbounded recursion, stack consumption, gain elevated privileges or cause hypervisor crash.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.5.0 - 4.9.0

CPE2.3

External links

http://xenbits.xen.org/xsa/advisory-240.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.