Security readout for executives and security teams
Plain-English summary
CVE-2021-33576 affects Cleo LexiCom 5.5.0.0. An AS2 message can name a file using path-traversal characters, causing LexiCom to write that file outside the intended location. Business urgency depends on whether LexiCom AS2 is deployed and who can send messages to it.
Executive priority
Prioritize if Cleo LexiCom 5.5.0.0 handles partner AS2 traffic. Treat as urgent for internet-facing or broadly reachable deployments because arbitrary file writes can materially affect system integrity.
Technical view
The issue is a path traversal in AS2 filename handling in Cleo LexiCom 5.5.0.0. The provided CVE description says a sender-controlled filename may allow arbitrary disk writes. The sources do not provide CVSS, CWE, authentication requirements, patch details, or confirmed exploitation.
Likely exposure
Organizations using Cleo LexiCom 5.5.0.0 with AS2 message handling are the likely exposure group. Exposure is higher if AS2 endpoints accept messages from external or weakly controlled partners.
Exploitation context
The source bundle does not show CISA KEV listing or any cited evidence of active exploitation. Exploitation would require the ability to submit an AS2 message that LexiCom processes. Impact depends on filesystem permissions and writable paths.
Researcher notes
Evidence is limited to the CVE description and referenced advisory/product pages in the bundle. The affected version and vulnerability mechanism are clear, but severity scoring, exploit maturity, authentication context, and remediation details are not provided.
Mitigation direction
- Inventory Cleo LexiCom deployments and confirm whether version 5.5.0.0 is present.
- Check Cleo and Atredis guidance for fixed versions or vendor-approved mitigations.
- Limit AS2 message submission to trusted partners and expected network paths.
- Review filesystem permissions for LexiCom to reduce arbitrary write impact.
- Monitor for unexpected files written outside configured AS2 storage locations.
Validation and detection
- Confirm installed LexiCom versions from asset records or application administration data.
- Identify AS2 endpoints and who is allowed to submit messages.
- Review recent AS2 processing logs for unusual filenames or path traversal patterns.
- Inspect LexiCom-owned directories and adjacent paths for unexpected file writes.
- Document whether vendor guidance confirms a patch or compensating control.
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.
CVE-2021-33576 mapping review
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Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/atredispartners/advisories/blob/master/ATREDIS-2020-0011.mdCVE reference · x_refsource_MISC
- https://www.cleo.com/cleo-lexicomCVE 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.