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TI-2021-03547 Aliases CVE-2021-20255GHSA-v6w7-gq3g-fwvm

Infinite loop in QEMU

Priority LOW 25CWE-835Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Will not fix Red Hat: no fix planned

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-835.

Summary

A stack overflow via an infinite recursion vulnerability was found in the eepro100 i8255x device emulator of QEMU. This issue occurs while processing controller commands due to a DMA reentry issue. This flaw allows a guest user or process to consume CPU cycles or crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Why it matters now

EPSS 0.00411 35th percentileScored 2026-11-07
Fix Will not fix Red Hat: no fix planned

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
—QEMUall versions—No fix listedCNA
  • QEMU Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*all versionsVulnerableQEMU
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
  • cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·QEMU
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Not affected: 5 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 8 Advanced Virtualization
  • Red Hat OpenStack Platform 10 (Newton)
  • Red Hat OpenStack Platform 13 (Queens)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-20255
  2. 2026-10-03 Alias added: GHSA-v6w7-gq3g-fwvm

References

Patch 2

Advisory 3

Sources

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