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TI-2021-03549 Aliases CVE-2021-20257GHSA-j586-x8f6-9xf2

Infinite loop in QEMU

Priority LOW 29CWE-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
Partial Red Hat: 3 fixed, 5 without a fix

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

Summary

An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Why it matters now

EPSS 0.0037 31st percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 3 fixed, 5 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
—QEMUFixed-In v6.2.0—No fix listedCNA
  • QEMU Vendor— Affected Fixed-In v6.2.0 Fixed in — No fix listed CNA

CPE configurations NVD · 14

CPEVersionsRoleVendor
cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*before 6.2.0VulnerableQEMU
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
cpe:2.3:a:redhat:openstack_platform:10.0:*:*:*:*:*:*:*10.0VulnerableRed Hat
cpe:2.3:a:redhat:openstack_platform:13.0:*:*:*:*:*:*:*13.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*6.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:a:redhat:codeready_linux_builder:-:*:*:*:*:*:*:*not specified by NVDVulnerableRed Hat
  • cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:* Versions before 6.2.0 Vulnerable ·QEMU
  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
  • cpe:2.3:a:redhat:openstack_platform:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:openstack_platform:13.0:*:*:*:*:*:*:* Versions 13.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:a:redhat:codeready_linux_builder:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Red Hat
Show 4 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*8.0Running onRed Hat
cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:*8.0Running onRed Hat
cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:*8.0Running onRed Hat
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Running on ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:* Versions 8.0 Running on ·Red Hat
  • cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* Versions 8.0 Running on ·Red Hat
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

Red Hat 2 advisories

  • RHSA-2022:0081 Released 2022-01-11 · Red Hat rating Low
    virt:av and virt-devel:av security and bug fix update
    • Advanced Virtualization for RHEL 8.5.0.Z SLOF-20210217-1.module+el8.5.0+10946+35bb3930.noarch::virt:av, SLOF-20210217-1.module+el8.5.0+10946+35bb3930.src::virt-devel:av, SLOF-20210217-1.module+el8.5.0+10946+35bb3930.src::virt:av +47
  • RHSA-2021:5238 Released 2021-12-21 · Red Hat rating Low
    virt:rhel and virt-devel:rhel security update
    • Red Hat CodeReady Linux Builder (v. 8) SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.src::virt-devel:rhel, hivex-1.3.18-21.module+el8.5.0+10709+b3edb581.i686::virt-devel:rhel, hivex-devel-1.3.18-21.module+el8.5.0+10709+b3edb581.i686::virt-devel:rhel +47
    • Red Hat Enterprise Linux AppStream (v. 8) SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.noarch::virt:rhel, SLOF-20191022-3.git899d9883.module+el8.3.0+6423+e4cb6418.src::virt:rhel, hivex-1.3.18-21.module+el8.5.0+10709+b3edb581.aarch64::virt:rhel +47

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
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8 Advanced VirtualizationAffectedNo fix yet
Red Hat OpenStack Platform 10 (Newton)AffectedNo fix planned: Out of support scope
Red Hat OpenStack Platform 13 (Queens)AffectedNo fix planned: Out of support scope
Advanced Virtualization for RHEL 8.5.0.ZFixed RHSA-2022:0081
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2021:5238
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:5238
Not affected: 1 product
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-20257
  2. 2026-10-03 Alias added: GHSA-j586-x8f6-9xf2

References

Patch 4

Advisory 3

Sources

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