Security readout for executives and security teams
Plain-English summary
This vulnerability can let an unauthenticated network attacker bypass login controls on a specific Reolink RLC-410W camera firmware version. The rated impact is limited because the CVSS vector indicates low integrity impact and no confidentiality or availability impact. Business urgency is highest where these cameras or their management interfaces are exposed beyond trusted networks.
Executive priority
Treat this as a moderate-priority exposure issue. Prioritize internet-facing or remotely managed cameras first, then internal devices on less trusted networks. The main business concern is unauthorized administrative access path risk, not confirmed widespread exploitation.
Technical view
CVE-2021-40404 is an authentication bypass in the cgiserver.cgi Login functionality of Reolink RLC-410W v3.0.0.136_20121102. The flaw is network-reachable, low complexity, requires no privileges or user interaction, and maps to CWE-284. Sources do not provide affected CPEs or a vendor fix in the supplied bundle.
Likely exposure
Exposure appears limited to Reolink RLC-410W devices running firmware v3.0.0.136_20121102, especially if camera web management is reachable from untrusted networks or the internet.
Exploitation context
The source bundle describes a specially crafted HTTP request that can trigger authentication bypass. It does not state active exploitation, and the CVE is not listed as KEV in the supplied data.
Researcher notes
The provided CVE metadata has incomplete affected-product fields, but the description identifies Reolink RLC-410W v3.0.0.136_20121102. Do not broaden scope without vendor evidence. Talos is the key technical reference in the bundle.
Mitigation direction
- Identify Reolink RLC-410W devices and confirm firmware versions.
- Check Reolink and Talos guidance for any vendor-approved firmware update or mitigation.
- Remove camera management interfaces from internet exposure.
- Restrict access to trusted admin networks or VPN-only paths.
- Monitor camera management logs for unexpected Login CGI activity.
Validation and detection
- Inventory deployed Reolink RLC-410W cameras and record firmware versions.
- Confirm whether any device runs v3.0.0.136_20121102.
- Review firewall and remote access rules for camera management access.
- Verify internet-facing exposure with approved asset discovery processes.
- Document whether vendor guidance or updated firmware is available.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-40404 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
5.3MediumVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1420CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.