| Name | CVE-2023-34328 |
| Description | [This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] AMD CPUs since ~2014 have extensions to normal x86 debugging functionality. Xen supports guests using these extensions. Unfortunately there are errors in Xen's handling of the guest state, leading to denials of service. 1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of a previous vCPUs debug mask state. 2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT. This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock up the CPU entirely. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| xen (PTS) | bullseye | 4.14.6-1 | vulnerable |
| bullseye (security) | 4.14.5+94-ge49571868d-1 | vulnerable |
| bookworm | 4.17.3+10-g091466ba55-1~deb12u1 | fixed |
| sid, trixie | 4.17.3+36-g54dacb5c02-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| xen | source | buster | (unfixed) | end-of-life | | |
| xen | source | bullseye | (unfixed) | end-of-life | | |
| xen | source | bookworm | 4.17.2+76-ge1f9cb16e2-1~deb12u1 | | | |
| xen | source | (unstable) | 4.17.2+55-g0b56bed864-1 | | | |
Notes
[bullseye] - xen <end-of-life> (EOLed in Bullseye)
[buster] - xen <end-of-life> (DSA 4677-1)
https://xenbits.xen.org/xsa/advisory-444.html