Security readout for executives and security teams
Plain-English summary
CVE-2020-3435 affects Cisco AnyConnect Secure Mobility Client for Windows. A user already signed in to a Windows machine could abuse the client’s IPC handling to overwrite VPN profile files. The main business concern is integrity of VPN configuration on managed endpoints, not remote takeover.
Executive priority
Treat this as a moderate endpoint hardening issue. It is not described as remotely exploitable, but unauthorized VPN profile modification can weaken trusted remote-access configuration and deserves remediation through standard patch and configuration management cycles.
Technical view
Cisco describes insufficient validation of user-supplied input in the Windows AnyConnect IPC channel. An authenticated local attacker with valid Windows credentials could send a crafted IPC message to the AnyConnect process, causing VPN profile files to be modified. CVSS 3.1 score is 5.5 with high integrity impact.
Likely exposure
Exposure is limited to Windows endpoints running Cisco AnyConnect Secure Mobility Client where an attacker already has local authenticated access. The supplied bundle does not identify exact affected or fixed versions.
Exploitation context
The supplied sources do not indicate active exploitation, and the CVE is not marked KEV. Exploitation requires valid local Windows credentials, so this is most relevant after account compromise, insider activity, or weak endpoint access controls.
Researcher notes
This is CWE-20 input validation in a local IPC path. The useful validation focus is product presence, Windows platform scope, installed version status against Cisco guidance, and evidence of unexpected VPN profile modification. Affected version detail is incomplete in the supplied bundle.
Mitigation direction
- Review the Cisco advisory for affected and fixed AnyConnect releases.
- Update affected Windows AnyConnect installations according to Cisco guidance.
- Restrict local Windows account access to managed endpoints.
- Monitor and control changes to AnyConnect VPN profile files.
- Prioritize endpoints used by privileged administrators or remote workforce users.
Validation and detection
- Inventory Windows endpoints with Cisco AnyConnect Secure Mobility Client installed.
- Compare installed AnyConnect versions against Cisco advisory guidance.
- Check whether VPN profile files changed unexpectedly.
- Review endpoint management logs for unauthorized AnyConnect configuration changes.
- Confirm local user access is limited to approved accounts.
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-20: 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 lookupCVE-2020-3435 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
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
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:N/I:H/A:N1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20200805 Cisco AnyConnect Secure Mobility Client for Windows Profile Modification 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.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.