Read the docs
TI-2021-02683 Aliases CVE-2021-3750GHSA-2v3x-7c37-r5r2

Use after free in QEMU

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 7 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A DMA reentrancy issue was found in the USB EHCI controller emulation of QEMU. EHCI does not verify if the Buffer Pointer overlaps with its MMIO region when it transfers the USB packets. Crafted content may be written to the controller's registers and trigger undesirable actions (such as reset) while the device is still transferring packets. This can ultimately lead to a use-after-free issue. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition, or potentially execute arbitrary code within the context of the QEMU process on the host. This flaw affects QEMU versions before 7.0.0.

Why it matters now

EPSS 0.00513 44th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 4 advisoriesRed Hat: 7 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
—QEMUQEMU before version 7.0.0—No fix listedCNA
  • QEMU Vendor— Affected QEMU before version 7.0.0 Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*before 7.0.0VulnerableQEMU
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:a:qemu:qemu:*:*:*:*:*:*:*:* Versions before 7.0.0 Vulnerable ·QEMU
  • 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

Remediation

Red Hat 4 advisories

  • RHSA-2024:0569 Released 2024-01-30 · Red Hat rating Moderate
    virt:rhel and virt-devel:rhel security update
    • Red Hat CodeReady Linux Builder EUS (v.8.8) SLOF-20210217-2.module+el8.8.0+20737+daad9f3b.src::virt-devel:rhel, hivex-1.3.18-23.module+el8.8.0+16781+9f4724c2.i686::virt-devel:rhel, hivex-devel-1.3.18-23.module+el8.8.0+16781+9f4724c2.i686::virt-devel:rhel +47
    • Red Hat Enterprise Linux AppStream EUS (v.8.8) SLOF-20210217-2.module+el8.8.0+20737+daad9f3b.noarch::virt:rhel, SLOF-20210217-2.module+el8.8.0+20737+daad9f3b.src::virt:rhel, hivex-1.3.18-23.module+el8.8.0+16781+9f4724c2.aarch64::virt:rhel +47
  • RHSA-2024:0404 Released 2024-01-25 · Red Hat rating Important
    virt:rhel and virt-devel:rhel security update
    • Red Hat CodeReady Linux Builder EUS (v.8.6) SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.src::virt-devel:rhel, hivex-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.i686::virt-devel:rhel, hivex-devel-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.i686::virt-devel:rhel +47
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.noarch::virt:rhel, SLOF-20210217-1.module+el8.6.0+14480+c0a3aa0f.src::virt:rhel, hivex-1.3.18-23.module+el8.6.0+14480+c0a3aa0f.aarch64::virt:rhel +47
  • RHSA-2023:6980 Released 2023-11-14 · Red Hat rating Moderate
    virt:rhel and virt-devel:rhel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) SLOF-20210217-1.module+el8.9.0+18724+20190c23.src::virt-devel:rhel, hivex-1.3.18-23.module+el8.9.0+18724+20190c23.i686::virt-devel:rhel, hivex-devel-1.3.18-23.module+el8.9.0+18724+20190c23.i686::virt-devel:rhel +47
    • Red Hat Enterprise Linux AppStream (v. 8) SLOF-20210217-1.module+el8.9.0+18724+20190c23.noarch::virt:rhel, SLOF-20210217-1.module+el8.9.0+18724+20190c23.src::virt:rhel, hivex-1.3.18-23.module+el8.9.0+18724+20190c23.aarch64::virt:rhel +47
Show 1 more Red Hat advisories
  • RHSA-2022:7967 Released 2022-11-15 · Red Hat rating Moderate
    qemu-kvm security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) qemu-guest-agent-17:7.0.0-13.el9, qemu-img-17:7.0.0-13.el9, qemu-kvm-17:7.0.0-13.el9 +19

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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 planned: Out of support scope
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
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2023:6980
Red Hat CodeReady Linux Builder EUS (v.8.6)Fixed RHSA-2024:0404
Red Hat CodeReady Linux Builder EUS (v.8.8)Fixed RHSA-2024:0569
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2023:6980
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2022:7967
Red Hat Enterprise Linux AppStream EUS (v.8.6)Fixed RHSA-2024:0404
Red Hat Enterprise Linux AppStream EUS (v.8.8)Fixed RHSA-2024:0569

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3750
  2. 2026-10-03 Alias added: GHSA-2v3x-7c37-r5r2

References

Exploit 1

Advisory 4

Sources

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