CVE-2021-28702PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via…
- 7.6HighCVSS base score
- 0.44%Exploitation in 30 daysEPSS · top 61% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.
Timeline
ID reserved
By XEN
- 7 months later
· 7 months later
Published
- 3 years later
· 3 years 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 |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.6 | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.44% · top 61% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.6.
Affected products
References
References7
- https://xenbits.xenproject.org/xsa/advisory-386.txt (opens in a new tab)x_refsource_MISCx_transferred
- [oss-security] 20211007 Xen Security Advisory 386 v2 (CVE-2021-28702) - PCI devices with RMRRs not deassigned correctly (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- FEDORA-2021-80bbe7def0 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2021-0b7a484688 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2021-829f5f2f43 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- DSA-5017 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- GLSA-202208-23 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
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-2021-15359 (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-2021-28702)Record last updated .