Security readout for executives and security teams
Plain-English summary
This flaw lets a signed-in local Windows user abuse Cisco AnyConnect components to get SYSTEM-level code execution. It is not a remote internet attack, but it can turn ordinary endpoint access into full machine compromise on affected systems.
Executive priority
Treat as a high-priority endpoint hardening issue, especially in environments where AnyConnect is broadly deployed. The business risk is privilege escalation after initial local access, not direct remote compromise.
Technical view
CVE-2021-1237 affects Cisco AnyConnect Secure Mobility Client for Windows, specifically Network Access Manager and Web Security Agent components. Insufficient validation of runtime-loaded resources can allow DLL injection. CVSS 3.1 is 7.8, CWE-427, with local attack vector, low complexity, low privileges, and no user interaction.
Likely exposure
Exposure is limited to Windows systems running Cisco AnyConnect Secure Mobility Client with the affected components present. The provided sources do not name exact affected or fixed versions, so version exposure must be confirmed against Cisco’s advisory.
Exploitation context
The source describes authenticated local exploitation requiring valid Windows credentials. Successful exploitation can execute arbitrary code with SYSTEM privileges. The CVE is not listed as KEV, and the provided bundle contains no evidence of active exploitation.
Researcher notes
The key technical issue is unsafe runtime resource loading leading to DLL injection, mapped to CWE-427. Public source details are limited; avoid assuming affected versions, patch levels, or exploitation in the wild beyond the Cisco and CVE records.
Mitigation direction
- Review Cisco’s advisory for affected and fixed release guidance.
- Inventory Windows AnyConnect deployments and installed components.
- Apply Cisco-supported updates or workarounds where applicable.
- Prioritize endpoints used by administrators or privileged users.
- Monitor endpoint alerts for local privilege escalation behavior.
Validation and detection
- Confirm whether AnyConnect is installed on Windows endpoints.
- Check for Network Access Manager or Web Security Agent components.
- Compare installed versions against Cisco’s advisory.
- Verify remediation through endpoint inventory after changes.
- Document systems where exposure cannot yet be determined.
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-2021-1237 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
- 20210113 Cisco AnyConnect Secure Mobility Client for Windows DLL Injection 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.
