TI-2021-09766 Aliases CVE-2021-28700 GHSA-whw9-2rv6-633x

Resource allocation without limits in xen

LOW 26CWE-770Published 2021-08-27 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: High
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.

Summary

xen/arm: No memory limit for dom0less domUs The dom0less feature allows an administrator to create multiple unprivileged domains directly from Xen. Unfortunately, the memory limit from them is not set. This allow a domain to allocate memory beyond what an administrator originally configured.

Why it matters now

EPSS 0.0187 79th percentileScored 2026-11-08

Fix Fixed xen (Xen): next of xen-unstable

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Xen	xen	4.12.x	—	No fix listed	CNA
Xen	xen	4.13.x and later	next of xen-unstable	Patch available	CNA

xen VendorXen Affected 4.12.x Fixed in — No fix listed CNA
xen VendorXen Affected 4.13.x and later Fixed in next of xen-unstable Patch available CNA

CPE configurations NVD · 5

CPE	Versions	Role	Vendor
cpe:2.3:o:xen:xen:::::::arm:*	4.12.0	Vulnerable	Xen
cpe:2.3:o:fedoraproject:fedora:33:::::::*	33	Vulnerable	Fedoraproject
cpe:2.3:o:fedoraproject:fedora:34:::::::*	34	Vulnerable	Fedoraproject
cpe:2.3:o:fedoraproject:fedora:35:::::::*	35	Vulnerable	Fedoraproject
cpe:2.3:o:debian:debian_linux:11.0:::::::*	11.0	Vulnerable	Debian

cpe:2.3:o:xen:xen:*:*:*:*:*:*:arm:* Versions 4.12.0 Vulnerable ·Xen
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* Versions 35 Vulnerable ·Fedoraproject
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian

Remediation

Fix · CNA xen (Xen) Fixed in next of xen-unstable

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Advisory · 2021-08-27
xen — FEDORA-2021-081f9bf5d2
7 records Highest priority Priority LOW 7 LOW
Other records, highest priority first
- TI-2021-09763 Race condition in xenPriority LOW 34
- TI-2021-09762 Incorrect authorization in xenPriority LOW 30
- TI-2021-09761 IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs…Priority LOW 30
Show all 7 records → Advisory →
Advisory · 2021-08-27
xen — FEDORA-2021-d68ed12e46
7 records Highest priority Priority LOW 7 LOW
Other records, highest priority first
- TI-2021-09763 Race condition in xenPriority LOW 34
- TI-2021-09762 Incorrect authorization in xenPriority LOW 30
- TI-2021-09761 IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs…Priority LOW 30
Show all 7 records → Advisory →

Show 2 more groups

Advisory · 2021-08-27
xen — FEDORA-2021-4f129cc0c1
7 records Highest priority Priority LOW 7 LOW
Other records, highest priority first
- TI-2021-09763 Race condition in xenPriority LOW 34
- TI-2021-09762 Incorrect authorization in xenPriority LOW 30
- TI-2021-09761 IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs…Priority LOW 30
Show all 7 records → Advisory →
Advisory · 2021-08-27
xen — DSA-4977
7 records Highest priority Priority LOW 7 LOW
Other records, highest priority first
- TI-2021-09763 Race condition in xenPriority LOW 34
- TI-2021-09762 Incorrect authorization in xenPriority LOW 30
- TI-2021-09761 IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs…Priority LOW 30
Show all 7 records → Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2021-28700
2026-10-03 Alias added: GHSA-whw9-2rv6-633x

References

Advisory 6

TI-2012-00210 The x86-64 kernel system-call functionality in Xen 4.1.2 and earlier, as used in Citrix… CVSS 2.0HIGH 7.2
TI-2023-07042 Information disclosure through error messages in AMD Ryzen™ 3000 Series Desktop… CVSS 3.1MEDIUM 5.5
TI-2015-04333 The C+ mode offload emulation in the RTL8139 network card device model in QEMU, as used… CVSS 2.0HIGH 9.3
TI-2015-06741 The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows… CVSS 3.1CRITICAL 10.0
TI-2018-06436 A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures… CVSS 3.0HIGH 7.8
TI-2024-20522 x86: Incorrect logic for BTC/SRSO mitigations CVSS 3.1HIGH 7.5

See all 489 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences