An issue was discovered in Xen through 4.9.x. Grant copying code made an implication that any grant pin would be accompanied by a suitable page reference. Other portions of code, however, did not match up with that assumption. When such a grant copy operation is being done on a grant of a dying domain, the assumption turns out wrong. A malicious guest administrator can cause hypervisor memory corruption, most likely resulting in host crash and a Denial of Service. Privilege escalation and information leaks cannot be ruled out.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
| Link | Tags |
|---|---|
| http://xenbits.xen.org/xsa/advisory-236.html | issue tracking patch vendor advisory |
| http://www.securityfocus.com/bid/101564 | issue tracking vdb entry third party advisory |
| http://www.openwall.com/lists/oss-security/2017/10/24/3 | issue tracking mailing list mitigation third party advisory |
| https://www.debian.org/security/2017/dsa-4050 | vendor advisory |
| https://support.citrix.com/article/CTX229057 | issue tracking third party advisory |
| http://www.securitytracker.com/id/1039653 | issue tracking vdb entry third party advisory |
| https://lists.debian.org/debian-lts-announce/2018/10/msg00009.html | mailing list |