Security readout for executives and security teams
Plain-English summary
This is a Windows local privilege escalation issue in Cisco security products. A logged-in attacker could abuse unsafe DLL loading to run code with SYSTEM privileges. It matters because endpoint security software runs with high trust, but exploitation requires existing local access and valid credentials.
Executive priority
Prioritize remediation on shared workstations, servers, and high-value endpoints where local compromise could become full SYSTEM control. This is not described as remotely exploitable, but it can materially worsen an existing foothold.
Technical view
CVE-2021-1386 is a CWE-427 DLL search path validation flaw affecting Cisco AMP for Endpoints Windows Connector, ClamAV for Windows, and Immunet. The CVSS 3.1 score is 7.0. The attack is local, high complexity, requires low privileges, no user interaction, and can yield SYSTEM-level code execution.
Likely exposure
Exposure is limited to Windows systems running the named Cisco endpoint products. The source bundle does not provide affected version ranges, so teams must compare deployed versions against Cisco’s advisory.
Exploitation context
The bundle states exploitation requires valid local credentials and placing a malicious DLL on the affected system. KEV is false, and the provided sources do not state active exploitation in the wild.
Researcher notes
The key behavior is insecure runtime directory search path validation. Validate exposure through product presence, version status, and writable path review. Avoid assuming exploit availability or affected versions beyond the sources.
Mitigation direction
- Review Cisco’s advisory for affected and fixed versions.
- Apply vendor-recommended updates or workarounds where applicable.
- Restrict local interactive access to affected Windows endpoints.
- Limit write permissions in product and service-related directories.
- Monitor for suspicious DLL creation near endpoint security components.
Validation and detection
- Inventory Windows endpoints running the named Cisco products.
- Compare installed versions with Cisco’s advisory.
- Check whether local users can write to sensitive product paths.
- Review EDR logs for unexpected DLL loads by security processes.
- Confirm endpoint security services are running supported versions.
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-2021-1386 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 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/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:H/PR:L/UI:N/S:U/C:H/I:H/A:H15.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7HighVector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20210407 Cisco Advanced Malware Protection for Endpoints Windows Connector, ClamAV for Windows, and Immunet 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.
