Null pointer dereference in xen (Alpine package)

1) Null pointer dereference

EUVDB-ID: #VU8425

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-14318

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

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

The weakness exists due to NULL pointer deference in certain GNTTABOP_cache_flush grant table operations. If exploited on x86-based PV guest systems without SMAP enabled, an adjacent attacker can gain elevated privileges. If exploited on ARM-based guest systems and x86-based PV guest systems that have SMAP enabled, an adjacent attacker can cause the host system to crash.

Mitigation

Install update from vendor's website.

Vulnerable software versions

xen (Alpine package): 4.5.0-r0 - 4.6.3-r10

External links

http://git.alpinelinux.org/aports/commit/?id=9616306fb5e4218fa8039e04e2f98e34a36fdf74
http://git.alpinelinux.org/aports/commit/?id=902758ce76df95964c0d12e7cea24d7013cecf81
http://git.alpinelinux.org/aports/commit/?id=9e8bfa9f6da89fa610692d159505391749ab3bdf
http://git.alpinelinux.org/aports/commit/?id=37a17c61fd9573ea51e77597bf4cd57b127d48ea
http://git.alpinelinux.org/aports/commit/?id=ccc49b6e6d7e85267b83fd27bbbc66cd4c17417a

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.