Description
The do_mmu_update function in arch/x86/mm.c in Xen 4.x through 4.4.x does not properly restrict updates to only PV page tables, which allows remote PV guests to cause a denial of service (NULL pointer dereference) by leveraging hardware emulation services for HVM guests using Hardware Assisted Paging (HAP).
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | xen | 4.4.1-4 | — |
| Debian 13 | xen | 4.4.1-4 | — |
| Debian 12 | xen | 4.4.1-4 | — |
| Debian 7 | xen | 4.1.4-3+deb7u4 | DSA-3140-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | xen | 4.4.1-0ubuntu0.14.04.2 | — |
Advisories 1
- DSA-3140-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- GLSA-201504-04 vendor-advisory
- 62672 third-party-advisory
- http://xenbits.xen.org/xsa/advisory-109.html
- 71149 vdb-entry
- DSA-3140 vendor-advisory
- openSUSE-SU-2015:0226 vendor-advisory
- openSUSE-SU-2015:0256 vendor-advisory
- xen-cve20148594-sec-byass(98767) vdb-entry