#VU7503 Null pointer dereference in Xen - CVE-2017-10917

Vulnerability identifier: #VU7503

Vulnerability risk: Low

CVSSv4.0: 5.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/U:Clear]

CVE-ID: CVE-2017-10917

CWE-ID: CWE-476

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Xen
Server applications / Virtualization software

Vendor: Xen Project

Description
The vulnerability allows a local attacker to cause DoS conditions.

The weakness exists due to improper validation of the port numbers of polled event channel ports. A local attacker can trigger NULL pointer dereference and cause the system to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Xen: 3.4.4 - 4.8.1

---

External links
https://xenbits.xen.org/xsa/advisory-218.html

---

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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