CVE-2021-40423

highpriority · track · 30EPSS 0.013 · 71 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.34% (71st) EPSS

CVSS 7.8 · high

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

A denial of service vulnerability exists in the cgiserver.cgi API command parser functionality of Reolink RLC-410W v3.0.0.136_20121102. A specially-crafted series of HTTP requests can lead to denial of service. An attacker can send an HTTP request to trigger this vulnerability.

cvss

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

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · talos-cna@cisco.com USexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimary

affected products (2)

Products and version ranges known to be affected.

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

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

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

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+25197 more

references (7)

External citations — patches, advisories, analysis.

https://nvd.nist.gov/vuln/detail/CVE-2021-40423 cnnvd
https://reolink.com/us/product/rlc-410w/Patchcnnvd
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1432 cnnvd
https://talosintelligence.com/vulnerability_reports/TALOS-2022-1432 cnnvd
https://talosintelligence.com/vulnerability_reports/TALOS-2022-1432 enisa_euvd
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1432ExploitTechnical DescriptionThird Party Advisorynvd
https://talosintelligence.com/vulnerability_reports/TALOS-2022-1432Broken LinkTechnical DescriptionThird Party Advisorynvd

scry

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