Security readout for executives and security teams
Plain-English summary
Some WAGO managed switches may store web UI user credentials inside browser cookies. If an attacker can obtain those cookies, they may learn credentials. The issue is rated medium, but it matters because switches often sit in operational networks where exposed management access can affect response and segmentation.
Executive priority
Treat this as a moderate operational technology hygiene issue. Prioritize internet-exposed or broadly reachable management interfaces first, then validate firmware and credential handling through normal change control.
Technical view
CVE-2021-20995 is CWE-312: cleartext storage of sensitive information. The CVE states that webserver cookies for the WAGO web-based UI contain user credentials. CVSS 3.1 is 5.3, network-accessible with low complexity and confidentiality impact only.
Likely exposure
Exposure is limited to listed WAGO managed switch models with web-based UI use. The source bundle does not identify affected firmware versions, internet exposure prevalence, or patch levels.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. Risk depends on whether attackers can access, intercept, steal, or inspect browser cookies from administrators managing affected switches.
Researcher notes
Evidence is concise but incomplete. The CVE names affected models and weakness type, but the provided bundle does not include exact affected versions, fixed versions, or confirmed exploitation. Avoid assuming broader WAGO product impact.
Mitigation direction
- Review the WAGO/VDE advisory for fixed firmware or vendor configuration guidance.
- Restrict switch web UI access to trusted admin networks or VPN only.
- Avoid shared or untrusted browsers for switch administration.
- Clear sessions and browser cookies after administering affected switches.
- Rotate web UI credentials after applying vendor-approved remediation.
Validation and detection
- Inventory WAGO switch models 0852-0303, 0852-1305, 0852-1505, and listed variants.
- Confirm firmware and product status against the VDE advisory.
- Check whether administrative cookies contain credentials during controlled defensive testing.
- Verify the web management interface is not reachable from untrusted networks.
- Check credential rotation records for affected switch administrator accounts.
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-312: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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 lookupCVE-2021-20995 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 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://cert.vde.com/en-us/advisories/vde-2021-013CVE reference · x_refsource_CONFIRM
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.
Cleartext Storage of Sensitive Information
Cleartext Storage of Sensitive Information represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.