Security readout for executives and security teams
Plain-English summary
This flaw lets an unauthenticated remote attacker read arbitrary files from an affected WirelessHART-Gateway server through a path traversal issue. The business risk is exposure of sensitive configuration or system files from industrial gateway equipment, not direct code execution based on the provided sources.
Executive priority
Treat as high priority for exposed industrial gateways because attackers may read sensitive files without credentials. Prioritize externally reachable systems first, then broad internal access paths.
Technical view
CVE-2021-33555 is a CWE-22 path traversal vulnerability in the filename parameter of PEPPERL+FUCHS WirelessHART-Gateway <= 3.0.7. The source bundle lists Phoenix Contact WHA-GW-F2D2-0-AS-Z2-ETH and WHA-GW-F2D2-0-AS-Z2-ETH.EIP version 3.0.7 as affected. CVSS 3.1 is 7.5, with network, low-complexity, no-auth exploitation and high confidentiality impact.
Likely exposure
Exposure is most likely where affected WirelessHART-Gateway devices are running version 3.0.7 or earlier and are reachable over a network by untrusted users. Internet exposure or broad internal access would increase urgency.
Exploitation context
The provided sources do not show CISA KEV listing or confirmed active exploitation. The CVSS vector indicates unauthenticated remote exploitation is possible with low attack complexity, but the documented impact is file disclosure only.
Researcher notes
Evidence is limited to the CVE data and CERT@VDE reference in the bundle. There is a naming mismatch: the description references PEPPERL+FUCHS WirelessHART-Gateway, while affected products list Phoenix Contact WHA-GW models. Confirm vendor lineage before scoping remediation.
Mitigation direction
- Review CERT@VDE VDE-2021-027 and vendor guidance for fixed firmware or mitigations.
- Remove internet exposure for affected gateway management services.
- Restrict access to trusted administrative networks or VPN users.
- Segment industrial gateways from general user networks.
- Monitor for suspicious file access or traversal-like requests.
Validation and detection
- Inventory WirelessHART-Gateway deployments and confirm product and firmware version.
- Identify any devices matching the listed Phoenix Contact WHA-GW models on version 3.0.7.
- Verify management interfaces are not reachable from the internet or untrusted networks.
- Review vendor advisory status for applicable updates or compensating controls.
- Check logs for unusual filename parameter access patterns without testing exploit payloads.
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-22: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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 lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-33555 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
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:H/I:N/A:N3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://cert.vde.com/en-us/advisories/vde-2021-027CVE 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.