Security readout for executives and security teams
Plain-English summary
This flaw affects Cisco Webex Teams on Windows. A local user with valid Windows credentials could make the client load an attacker-controlled library when the app starts, causing code to run as another user account. This is a serious endpoint risk, but the provided sources do not show active exploitation.
Executive priority
Treat as a high-priority endpoint hygiene issue for organizations using Webex Teams on Windows, especially shared workstations or environments with many local users. It is not remotely exploitable based on the provided sources.
Technical view
CVE-2020-3535 is a CWE-427 DLL hijacking issue caused by incorrect runtime directory path handling in Cisco Webex Teams Client for Windows. Exploitation requires authenticated local access. Successful exploitation can execute arbitrary code on the targeted Windows system with another user account’s privileges.
Likely exposure
Exposure is limited to Windows systems running Cisco Webex Teams Client. The provided bundle does not identify affected or fixed version numbers, so teams must verify installed versions against Cisco’s advisory.
Exploitation context
The attacker must already have valid credentials on the Windows system. The source bundle says exploitation involves placing a malicious DLL where the client may load it. KEV is false, and no cited source confirms active exploitation.
Researcher notes
The strongest evidence is Cisco’s advisory and the CVE record. Key gaps are exact affected versions, fixed versions, and any workaround details, which are not included in the source bundle. Do not assume exploitation in the wild without further sourced evidence.
Mitigation direction
- Review Cisco’s advisory and apply the fixed Webex Teams for Windows release it identifies.
- Remove unsupported or unneeded Webex Teams installations from Windows endpoints.
- Limit local user write permissions in application and shared directories.
- Monitor Webex Teams process launches and unexpected DLL loads.
Validation and detection
- Inventory Windows endpoints with Cisco Webex Teams installed.
- Compare installed client versions against Cisco advisory affected and fixed release guidance.
- Review EDR logs for unexpected DLL loads associated with Webex Teams.
- Confirm local users cannot write to sensitive application directories.
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-427: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2020-3535 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/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:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20201007 Cisco Webex Teams Client for Windows DLL Hijacking VulnerabilityCVE reference · vendor-advisory, x_refsource_CISCO
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.
Uncontrolled Search Path Element
Uncontrolled Search Path Element represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
