Skip to content
Noroxi
CVE-2020-35517· NVD / CVE Program· CNA redhat

A flaw was found in qemu.

A flaw was found in qemu. A host privilege escalation issue was found in the virtio-fs shared file system daemon where a privileged guest user is able to create a device special file in the shared directory and use it to r/w access host devices.

HighCVSS 8.2 · v3.1—No exploit Fix available
Published
Jan 28, 2021
Updated
Jun 16, 2026
EPSS
0.5% · 42th percentile
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
32 / 40 · 8.2 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

Affected systems

VendorProduct
qemuqemu

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • qemu qemu5.0.0 and later · up to 5.2.50 inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a qemu

    • qemu 5.2.0affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:8hivexbefore 1.3.18-20.module_el8.3.0+2048+e7a0a3ea1.3.18-20.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8hivex-develbefore 1.3.18-20.module_el8.3.0+2048+e7a0a3ea1.3.18-20.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libguestfs-winsupportbefore 8.2-1.module_el8.3.0+2048+e7a0a3ea8.2-1.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libguestfs-winsupportbefore 8.2-1.module_el8.5.0+2608+720633658.2-1.module_el8.5.0+2608+72063365
AlmaLinux:8libiscsibefore 1.18.0-8.module_el8.5.0+2608+720633651.18.0-8.module_el8.5.0+2608+72063365
AlmaLinux:8libiscsibefore 1.18.0-8.module_el8.6.0+2880+7d9e37031.18.0-8.module_el8.6.0+2880+7d9e3703
AlmaLinux:8libiscsibefore 1.18.0-8.module_el8.3.0+2048+e7a0a3ea1.18.0-8.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libiscsi-develbefore 1.18.0-8.module_el8.6.0+2880+7d9e37031.18.0-8.module_el8.6.0+2880+7d9e3703
AlmaLinux:8libiscsi-develbefore 1.18.0-8.module_el8.5.0+2608+720633651.18.0-8.module_el8.5.0+2608+72063365
AlmaLinux:8libiscsi-develbefore 1.18.0-8.module_el8.3.0+2048+e7a0a3ea1.18.0-8.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libiscsi-utilsbefore 1.18.0-8.module_el8.5.0+2608+720633651.18.0-8.module_el8.5.0+2608+72063365
AlmaLinux:8libiscsi-utilsbefore 1.18.0-8.module_el8.6.0+2880+7d9e37031.18.0-8.module_el8.6.0+2880+7d9e3703
AlmaLinux:8libiscsi-utilsbefore 1.18.0-8.module_el8.3.0+2048+e7a0a3ea1.18.0-8.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libnbdbefore 1.2.2-1.module_el8.5.0+2608+720633651.2.2-1.module_el8.5.0+2608+72063365
AlmaLinux:8libnbdbefore 1.2.2-1.module_el8.3.0+2048+e7a0a3ea1.2.2-1.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libnbd-develbefore 1.2.2-1.module_el8.3.0+2048+e7a0a3ea1.2.2-1.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libnbd-develbefore 1.2.2-1.module_el8.5.0+2608+720633651.2.2-1.module_el8.5.0+2608+72063365
AlmaLinux:8libvirtbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-adminbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-bash-completionbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-clientbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-daemonbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-daemon-config-networkbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea
AlmaLinux:8libvirt-daemon-config-nwfilterbefore 6.0.0-28.module_el8.3.0+2048+e7a0a3ea6.0.0-28.module_el8.3.0+2048+e7a0a3ea

+96

Same product

qemu: all records

Other highest-scoring records for the same primary product.

  • CVE-2019-12928The QMP migrate command in QEMU version 4.0.0 and earlier is vulnerable to OS command injection, which allows the remote attacker to achieve
    46Plan
  • CVE-2015-8556Local privilege escalation vulnerability in the Gentoo QEMU package before 2.5.0-r1.
    44Plan
  • CVE-2017-15118A stack-based buffer overflow vulnerability was found in NBD server implementation in qemu before 2.11 allowing a client to request an expor
    43Plan
  • CVE-2022-36648The hardware emulation in the of_dpa_cmd_add_l2_flood of rocker device model in QEMU, as used in 7.0.0 and earlier, allows remote attackers
    41Plan
  • CVE-2017-16845hw/input/ps2.c in Qemu does not validate 'rptr' and 'count' values during guest migration, leading to out-of-bounds access.
    41Plan
  • CVE-2016-7161Heap-based buffer overflow in the .receive callback of xlnx.xps-ethernetlite in QEMU (aka Quick Emulator) allows attackers to execute arbitr
    41Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
almalinux:hivex1.3.18-20.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:hivex-devel1.3.18-20.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libguestfs-winsupport8.2-1.module_el8.5.0+2608+72063365 · AlmaLinux:8Package registry (OSV)
almalinux:libiscsi1.18.0-8.module_el8.6.0+2880+7d9e3703 · AlmaLinux:8Package registry (OSV)
almalinux:libiscsi-devel1.18.0-8.module_el8.6.0+2880+7d9e3703 · AlmaLinux:8Package registry (OSV)
almalinux:libiscsi-utils1.18.0-8.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libnbd1.2.2-1.module_el8.5.0+2608+72063365 · AlmaLinux:8Package registry (OSV)
almalinux:libnbd-devel1.2.2-1.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libvirt6.0.0-28.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libvirt-admin6.0.0-28.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libvirt-bash-completion6.0.0-28.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
almalinux:libvirt-client6.0.0-28.module_el8.3.0+2048+e7a0a3ea · AlmaLinux:8Package registry (OSV)
debian:qemu1:5.2+dfsg-5 · Debian:12Package registry (OSV)
red hat:hivex0:1.3.18-20.module+el8.3.0+6124+819ee737 · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:hivex-debuginfo0:1.3.18-20.module+el8.3.0+6124+819ee737 · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:hivex-debugsource0:1.3.18-20.module+el8.3.0+6124+819ee737 · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:hivex-devel0:1.3.18-20.module+el8.3.0+6124+819ee737 · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-bash-completion1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-debuginfo1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-debugsource1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-devel1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-gfs21:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:libguestfs-gobject1:1.42.0-2.module+el8.3.0+6798+ad6e66be · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
red hat:SLOF0:20200717-1.gite18ddad8.module+el8.3.0+7638+07cf13d2 · Red Hat:advanced_virtualization:8.3::el8Package registry (OSV)
rocky linux:hivex0:1.3.18-20.module+el8.4.0+534+4680a14e · Rocky Linux:8Package registry (OSV)
rocky linux:libguestfs-winsupport0:8.2-1.module+el8.4.0+534+4680a14e · Rocky Linux:8Package registry (OSV)
rocky linux:libiscsi0:1.18.0-8.module+el8.7.0+1084+97b81f61 · Rocky Linux:8Package registry (OSV)
rocky linux:libnbd0:1.2.2-1.module+el8.4.0+534+4680a14e · Rocky Linux:8Package registry (OSV)
rocky linux:libvirt-dbus0:1.3.0-2.module+el8.7.0+1084+97b81f61 · Rocky Linux:8Package registry (OSV)

+7

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Local
Attack complexity
Low
Privileges required
High
User interaction
None
Scope
Changed
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-269 · Improper Privilege Management

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

nvd-primary

Root cause

To simplify setup, a service account is granted broad, cluster-wide permissions. The principle of least privilege is skipped during installation.

The bug in code

The whole CWE-269 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

yaml
kind: ClusterRolerules:  - apiGroups: ["*"]    resources: ["*"]    verbs: ["*"]

Fixed

yaml
kind: Rolemetadata:  namespace: lodos-systemrules:  - apiGroups: ["apps"]    resources: ["deployments"]    verbs: ["get", "list", "update"]

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records