Back to CVE-2021-4156
How to verify CVE-2021-4156
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 33 NVT checks for CVE-2021-4156. 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='1.3.6.1.4.1.25623.1.0.854452' details='1'/>" NVT OIDs (33)
1.3.6.1.4.1.25623.1.0.854452since 2026-06-251.3.6.1.4.1.25623.1.0.854496since 2026-06-251.3.6.1.4.1.25623.1.0.893058since 2026-06-251.3.6.1.4.1.25623.1.0.893126since 2026-06-251.3.6.1.4.1.25623.1.1.11.2022.1968since 2026-06-251.3.6.1.4.1.25623.1.1.1.2.2022.3058since 2026-06-251.3.6.1.4.1.25623.1.1.1.2.2022.3126since 2026-06-251.3.6.1.4.1.25623.1.1.12.2022.5409.1since 2026-06-251.3.6.1.4.1.25623.1.1.1.2.2025.4402since 2026-06-251.3.6.1.4.1.25623.1.1.12.2025.7273.1since 2026-06-25
+ 23 more NVTs
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