Xen through 4.8.x does not validate the port numbers of polled event channel ports, which allows guest OS users to cause a denial of service (NULL pointer dereference and host OS crash) or possibly obtain sensitive information, aka XSA-221.
Weakness
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Xen | Xen | * | 4.8.1 (including) |
| Xen | Ubuntu | devel | * |
| Xen | Ubuntu | esm-infra/xenial | * |
| Xen | Ubuntu | trusty | * |
| Xen | Ubuntu | xenial | * |
| Xen | Ubuntu | yakkety | * |
| Xen | Ubuntu | zesty | * |
Potential Mitigations
References
- http://www.debian.org/security/2017/dsa-3969
- http://www.securityfocus.com/bid/99157
- http://www.securitytracker.com/id/1038731
- https://security.gentoo.org/glsa/201708-03
- https://xenbits.xen.org/xsa/advisory-221.html
- http://www.debian.org/security/2017/dsa-3969
- http://www.securityfocus.com/bid/99157
- http://www.securitytracker.com/id/1038731
- https://security.gentoo.org/glsa/201708-03
- https://xenbits.xen.org/xsa/advisory-221.html