CVE-2021-40408

highpriority · track · 40EPSS 0.037 · 90 %ileEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

3.66% (90th) EPSS

CVSS 7.5 · high

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

An OS command injection vulnerability exists in the device network settings functionality of reolink RLC-410W v3.0.0.136_20121102. At [1] or [2], based on DDNS type, the ddns->username variable, that has the value of the userName parameter provided through the SetDdns API, is not validated properly. This would lead to an OS command injection.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.09.1criticalCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:Hsecondary · ENISA EU

v3.09.1criticalCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:Hsecondary · talos-cna@cisco.com USexploitability 2.3 · impact 6

v3.18.8highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78US

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Reolink Reolink RLC-410W≤ 3.0.0.136_20121102fstec_bduRU
reolink rlc-410w firmware= 3.0.0.136_20121102nvdUScpe:2.3:o:reolink:rlc-410w_firmware:*:*:*:*:*:*:*:*

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2022-01-28modified 2026-06-17

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references (6)

External citations — patches, advisories, analysis.

scry

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