Security readout for executives and security teams
Plain-English summary
VISAM VBASE Pro-RT/Server-RT Web Remote 11.6.0.6 can place untrusted input into a public-facing webpage without proper neutralization, creating a cross-site scripting risk. The main concern is confidentiality: a victim may need to interact with malicious content for exposure to occur.
Executive priority
Treat as a moderate-priority confidentiality issue. It is not listed as known exploited in the provided sources, but public-facing industrial web access should be reviewed promptly.
Technical view
CVE-2021-42535 is CWE-79 cross-site scripting in VISAM VBASE Web Remote. CVSS 3.1 is 5.3: network reachable, high complexity, no privileges required, user interaction required, unchanged scope, high confidentiality impact, no integrity or availability impact.
Likely exposure
Exposure is limited to organizations running VISAM VBASE Pro-RT/Server-RT Web Remote version 11.6.0.6, especially where the web interface is reachable by users or the public.
Exploitation context
The supplied bundle does not show CISA KEV listing or active exploitation evidence. Exploitation is not automatic; the CVSS vector indicates high attack complexity and required user interaction.
Researcher notes
Evidence is narrow: the bundle identifies affected version, CWE-79, CVSS, and CISA advisory reference. It does not provide patch details, proof-of-concept status, or confirmed exploitation.
Mitigation direction
- Check VISAM and the CISA advisory for fixed versions or official configuration guidance.
- Prioritize remediation for any public-facing Web Remote deployment.
- Limit Web Remote access to trusted networks where business operations allow.
- Review whether exposed instances can be temporarily disabled until vendor guidance is applied.
Validation and detection
- Inventory VISAM VBASE Pro-RT/Server-RT Web Remote deployments.
- Confirm whether any instance runs version 11.6.0.6.
- Determine whether the Web Remote interface is public-facing or broadly reachable.
- Review compensating controls controlling user access to the web interface.
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-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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-2021-42535 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:H/PR:N/UI:R/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:H/PR:N/UI:R/S:U/C:H/I:N/A:N1.63.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.cisa.gov/uscert/ics/advisories/icsa-21-308-01CVE 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.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.