Multiple vulnerabilities in Xen

1) Input validation error

EUVDB-ID: #VU40645

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2015-7311

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to manipulate or delete data.

libxl in Xen 4.1.x through 4.6.x does not properly handle the readonly flag on disks when using the qemu-xen device model, which allows local guest users to write to a read-only disk image.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.1.0 - 4.5.1

CPE2.3

• cpe:2.3:a:xen_project:xen:4.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.1.2:*:*:*:*:*:*:*

External links

https://lists.fedoraproject.org/pipermail/package-announce/2015-September/167077.html
https://lists.fedoraproject.org/pipermail/package-announce/2015-September/167792.html
https://lists.fedoraproject.org/pipermail/package-announce/2015-September/167820.html
https://lists.opensuse.org/opensuse-updates/2015-12/msg00053.html
https://www.debian.org/security/2015/dsa-3414
https://www.securityfocus.com/bid/76823
https://www.securitytracker.com/id/1033633
https://xenbits.xen.org/xsa/advisory-142.html
https://bugzilla.redhat.com/show_bug.cgi?id=1257893
https://security.gentoo.org/glsa/201604-03

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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

2) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU40653

Risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2015-6654

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

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

The xenmem_add_to_physmap_one function in arch/arm/mm.c in Xen 4.5.x, 4.4.x, and earlier does not limit the number of printk console messages when reporting a failure to retrieve a reference on a foreign page, which allows remote domains to cause a denial of service by leveraging permissions to map the memory of a foreign guest.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.4.0 - 4.5.1

CPE2.3

• cpe:2.3:a:xen_project:xen:4.4.0:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.5.1:*:*:*:*:*:*:*

External links

https://www.debian.org/security/2015/dsa-3414
https://www.securitytracker.com/id/1033438
https://xenbits.xen.org/xsa/advisory-141.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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