Description
The xenlight library (libxl) in Xen 4.0.x through 4.2.x, when IOMMU is disabled, provides access to a busmastering-capable PCI passthrough device before the IOMMU setup is complete, which allows local HVM guest domains to gain privileges or cause a denial of service via a DMA instruction.
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 | 4.3.0-1 | — |
| Debian 13 | xen | 4.3.0-1 | — |
| Debian 12 | xen | 4.3.0-1 | — |
| Debian 7 | xen | 4.1.4-3+deb7u2 | DSA-3006-1 |
Advisories 1
- DSA-3006-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- [oss-security] 20130910 Re: Xen Security Advisory 61 - libxl partially sets up HVM passthrough even with disabled iommu mailing-list
- [Xen-devel] 20130701 [PATCH] libxl: suppress device assignment to HVM guest when there is no IOMMU mailing-list
- GLSA-201407-03 vendor-advisory
- SUSE-SU-2014:0446 vendor-advisory
- DSA-3006 vendor-advisory