Security readout for executives and security teams
Plain-English summary
CVE-2020-3240 affects Cisco UCS Director products and can let a remote unauthenticated attacker bypass authentication or perform directory traversal through the REST API. The CVSS 9.8 score reflects potential full confidentiality, integrity, and availability impact. The provided sources do not state active exploitation.
Executive priority
Treat this as urgent for any exposed Cisco UCS Director environment. The vulnerability has critical unauthenticated remote impact, but urgency depends on confirmed product presence, version status, and REST API exposure.
Technical view
The source bundle describes multiple REST API flaws in Cisco UCS Director and Cisco UCS Director Express for Big Data. The issue is classified as CWE-20 with network attack vector, low complexity, no privileges, and no user interaction. The bundle does not include affected version ranges or fixed release details.
Likely exposure
Exposure is most likely where Cisco UCS Director or UCS Director Express for Big Data REST API endpoints are reachable by untrusted networks. The bundle lists Cisco UCS Director and references Express for Big Data, but does not provide version-specific affected ranges.
Exploitation context
The CVE is not marked KEV in the provided bundle. The sources support unauthenticated remote attack potential, but they do not provide evidence of active exploitation, public exploitation, or observed campaigns.
Researcher notes
Evidence is limited to the CVE bundle, Cisco advisory reference, and ZDI reference. The bundle states authentication bypass and directory traversal in the REST API, but does not provide detailed affected version ranges, fixed versions, exploit maturity, or workaround text.
Mitigation direction
- Review Cisco’s advisory for affected releases and fixed software guidance.
- Apply Cisco-confirmed updates or workarounds where applicable.
- Restrict REST API access to trusted administrative networks.
- Remove internet exposure for UCS Director management interfaces.
- Increase monitoring for suspicious REST API access.
Validation and detection
- Inventory Cisco UCS Director and Express for Big Data deployments.
- Confirm installed versions against Cisco’s advisory.
- Check whether REST API endpoints are reachable externally.
- Review access logs for unusual unauthenticated REST API activity.
- Validate network controls restrict management access.
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
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CWE-20: Exact CWE lookup
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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-2020-3240 mapping review
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Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
9.8CriticalVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20200415 Multiple Vulnerabilities in Cisco UCS Director and Cisco UCS Director Express for Big DataCVE reference · vendor-advisory, x_refsource_CISCO
- https://www.zerodayinitiative.com/advisories/ZDI-20-542/CVE 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.