How to verify CVE-2021-28691

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 8 NVT checks for CVE-2021-28691. 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='1.3.6.1.4.1.25623.1.0.845001' details='1'/>"

NVT OIDs (8)

1.3.6.1.4.1.25623.1.0.845001since 2026-06-25
1.3.6.1.4.1.25623.1.0.845030since 2026-06-25
1.3.6.1.4.1.25623.1.0.845034since 2026-06-25
1.3.6.1.4.1.25623.1.1.10.2021.0257since 2026-06-25
1.3.6.1.4.1.25623.1.1.10.2021.0258since 2026-06-25
1.3.6.1.4.1.25623.1.1.12.2021.5015.1since 2026-06-25
1.3.6.1.4.1.25623.1.1.12.2021.5046.1since 2026-06-25
1.3.6.1.4.1.25623.1.1.12.2021.5050.1since 2026-06-25

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