How to verify CVE-2021-4091

Confirm whether your systems are actually affected — run the exact detection check below (Nuclei command or OpenVAS NVT). Detection only; it does not exploit.

Verify with OpenVAS

Greenbone/OpenVAS ships 21 NVT checks for CVE-2021-4091. OpenVAS detects this CVE by NVT OID — enable the NVT in your scan config, or confirm it is in your feed with the query below.

Confirm the NVT is in your feed (GMP)

gvm-cli socket --xml "<get_nvts nvt_oid='1.3.6.1.4.1.25623.1.0.854744' details='1'/>"

NVT OIDs (21)

1.3.6.1.4.1.25623.1.0.854744since 2026-06-25
1.3.6.1.4.1.25623.1.0.854789since 2026-06-25
1.3.6.1.4.1.25623.1.0.884207since 2026-06-25
1.3.6.1.4.1.25623.1.0.910788since 2026-06-25
1.3.6.1.4.1.25623.1.1.10.2022.0106since 2026-06-25
1.3.6.1.4.1.25623.1.1.11.2022.0628since 2026-06-25
1.3.6.1.4.1.25623.1.1.11.2022.0889since 2026-06-25
1.3.6.1.4.1.25623.1.1.1.2.2023.3399since 2026-06-25
1.3.6.1.4.1.25623.1.1.1.2.2025.4021since 2026-06-25
1.3.6.1.4.1.25623.1.1.14.2022.0889since 2026-06-25

+ 11 more NVTs

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