CVE-2023-46842x86 HVM hypercalls may trigger Xen bug check
- 6.5MediumCVSS base score
- 8.5%Exploitation in 30 daysEPSS · top 4.9% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Unlike 32-bit PV guests, HVM guests may switch freely between 64-bit and other modes. This in particular means that they may set registers used to pass 32-bit-mode hypercall arguments to values outside of the range 32-bit code would be able to set them to. When processing of hypercalls takes a considerable amount of time, the hypervisor may choose to invoke a hypercall continuation. Doing so involves putting (perhaps updated) hypercall arguments in respective registers. For guests not running in 64-bit mode this further involves a certain amount of translation of the values. Unfortunately internal sanity checking of these translated values assumes high halves of registers to always be clear when invoking a hypercall. When this is found not to be the case, it triggers a consistency check in the hypervisor and causes a crash.
Timeline
ID reserved
By XEN
- 7 months later
· 7 months later
Published
- 18 months later
· 18 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium6.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Analyzed | 3.1 | Medium6.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 8.5% · top 4.9% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Affected products
What to do
Workaround: Not using HVM / PVH guests will avoid the vulnerability.
References
References4
- https://xenbits.xenproject.org/xsa/advisory-454.html (opens in a new tab)x_transferred
- http://xenbits.xen.org/xsa/advisory-454.html (opens in a new tab)
- https://lists.fedoraproject.org/archives/list/[email protected]/message/D5OK6MH75S7YWD34EWW7QIZTS627RIE3/ (opens in a new tab)
- https://lists.fedoraproject.org/archives/list/[email protected]/message/RYAZ7P6YFJ2E3FHKAGIKHWS46KYMMTZH/ (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-51008 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-46842)Record last updated .