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Vulnerability details: VCID-eqp6-raqc-dkch
Vulnerability ID VCID-eqp6-raqc-dkch
Aliases CVE-2021-20181
Summary qemu: 9pfs: TOCTOU privilege escalation vulnerability
Status Published
Exploitability 0.5
Weighted Severity 6.8
Risk 3.4
Affected and Fixed Packages Package Details
Weaknesses (2)
CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
CWE-416 Use After Free
System Score Found at
cvssv3 7.5 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-20181.json
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
epss 0.00055 https://api.first.org/data/v1/epss?cve=CVE-2021-20181
cvssv3.1 7.5 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-20181.json
https://api.first.org/data/v1/epss?cve=CVE-2021-20181
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20181
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
1927007 https://bugzilla.redhat.com/show_bug.cgi?id=1927007
USN-4725-1 https://usn.ubuntu.com/4725-1/
No exploits are available.
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-20181.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.1716
EPSS Score 0.00055
Published At April 1, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-04-01T14:03:30.484567+00:00 RedHat Importer Import https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-20181.json 38.0.0