Security readout for executives and security teams
Plain-English summary
FusionPBX 4.5.7 has a directory traversal issue in folder deletion functionality. A remote malicious user may manipulate a folder value to delete folders on the system. Business impact could include service disruption or data loss, but the sources do not provide severity, authentication requirements, or exploitation evidence.
Executive priority
Treat as a targeted operational risk for FusionPBX deployments rather than a confirmed mass-exploitation emergency. Prioritize if FusionPBX 4.5.7 supports business voice services or is externally reachable.
Technical view
CVE-2020-21057 describes path traversal through the folder variable in app/edit/folderdelete.php, allowing folder deletion outside the intended scope. The public bundle identifies FusionPBX 4.5.7 and links a public report plus a FusionPBX commit. No CVSS, CWE, or complete affected product metadata is provided.
Likely exposure
Likely exposure is limited to environments running FusionPBX 4.5.7 where the affected folder deletion endpoint is reachable. The source bundle does not confirm whether authentication, administrative privileges, or specific configuration conditions are required.
Exploitation context
The CVE is not listed as CISA KEV in the provided bundle. Public technical references and a patch commit exist, but the supplied sources do not state active exploitation in the wild.
Researcher notes
Evidence is sparse: no CVSS, CWE, authentication context, or fixed release is included. The useful anchors are the affected script, the folder parameter, FusionPBX 4.5.7, the public report, and the referenced commit.
Mitigation direction
- Check current FusionPBX vendor guidance for the affected release and supported upgrade path.
- Review and apply the referenced FusionPBX fix where appropriate for your deployment.
- Restrict access to FusionPBX administrative or editing interfaces to trusted networks and users.
- Ensure recent backups exist for FusionPBX application files and dependent configuration data.
- Monitor for unexpected file or folder deletion around FusionPBX application paths.
Validation and detection
- Inventory FusionPBX instances and confirm whether version 4.5.7 is present.
- Determine whether app/edit/folderdelete.php is reachable from untrusted networks.
- Compare local code against the referenced FusionPBX commit.
- Review web and application logs for unusual folder deletion requests.
- Verify backup restoration for affected FusionPBX directories and configuration data.
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.
File 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-2020-21057 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
- 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://resp3ctblog.wordpress.com/2019/10/28/fusionpbx-path-traversal-4/CVE reference · x_refsource_MISC
- https://github.com/fusionpbx/fusionpbx/commit/026c3958c3c7ca6b2ff067addc991aac8f41cf11CVE 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.