You can configure exemptions to override an Always-On policy. For example, you might want to let certain individuals establish VPN sessions with other companies or exempt the Always-On policy for noncorporate assets.
Exemptions set in group policies and dynamic access policies on the ASA override the Always-On policy. You specify exceptions according to the matching criteria used to assign the policy. If an AnyConnect policy enables Always-On and a dynamic access policy or group policy disables it, the client retains the disable setting for the current and future VPN sessions as long as its criteria match the dynamic access policy or group policy on the establishment of each new session.
This procedure configures a dynamic access policy that uses AAA endpoint criteria to match sessions to noncorporate assets. This can occur when a secure gateway is unreachable, or when AnyConnect fails to detect the presence of a captive portal hotspot. An open policy permits full network access, letting users continue to perform tasks where access to the Internet or other local network resources is needed.
A closed policy disables all network connectivity until the VPN session is established. AnyConnect does this by enabling packet filters that block all traffic from the endpoint that is not bound for a secure gateway to which the computer is allowed to connect. Regardless of the connect failure policy, AnyConnect continues to try to establish the VPN connection.
Consider the following when using an open policy which permits full network access:. Security and protection are not available until the VPN session is established; therefore, the endpoint device may get infected with web-based malware or sensitive data may leak.
An open connect failure policy does not apply if you enable the Disconnect button and the user clicks Disconnect. Consider the following when using a closed policy which disables all network connectivity until the VPN session is established:. A closed policy can halt productivity if users require Internet access outside the VPN.
The purpose of closed is to help protect corporate assets from network threats when resources in the private network that protect the endpoint are not available. The endpoint is protected from web-based malware and sensitive data leakage at all times because all network access is prevented except for local resources such as printers and tethered devices permitted by split tunneling.
This option is primarily for organizations where security persistence is a greater concern than always-available network access. A closed policy prevents captive portal remediation unless you specifically enable it. For example, these rules could determine access to active sync and local printing. The network is unblocked and open during an AnyConnect software upgrade when Always-On is enabled regardless of a closed policy.
If you deploy a closed connection policy, we highly recommend that you follow a phased approach. For example, first deploy Always-On with a connect failure open policy and survey users for the frequency with which AnyConnect does not connect seamlessly. Then deploy a small pilot deployment of a connect failure closed policy among early-adopter users and solicit their feedback. Expand the pilot program gradually while continuing to solicit feedback before considering a full deployment.
As you deploy a connect failure closed policy, be sure to educate the VPN users about the network access limitation as well as the advantages of a connect failure closed policy. A connect failure closed policy prevents network access if AnyConnect fails to establish a VPN session.
Use extreme caution when implementing a connect failure closed policy. By default, the connect failure policy is closed, preventing Internet access if the VPN is unreachable. To allow Internet access in this situation the connect failure policy must be set to open. Set the Connect Failure Policy parameter to one of the following settings:. Closed— Default Restricts network access when the secure gateway is unreachable. Open—Permits network access by browsers and other applications when the client cannot connect to the secure gateway.
Configure Captive Portal Remediation. Many facilities that offer Wi-Fi and wired access, such as airports, coffee shops, and hotels, require the user to pay before obtaining access, to agree to abide by an acceptable use policy, or both. These facilities use a technique called captive portal to prevent applications from connecting until the user opens a browser and accepts the conditions for access.
Captive portal detection is the recognition of this restriction, and captive portal remediation is the process of satisfying the requirements of a captive portal hotspot in order to obtain network access.
Captive portals are detected automatically by AnyConnect when initiating a VPN connection requiring no additional configuration. Also, AnyConnect does not modify any browser configuration settings during captive portal detection and does not automatically remediate the captive portal.
It relies on the end user to perform the remediation. AnyConnect reacts to the detection of a captive portal depending on the current configuration:.
If Always-On is disabled, or if Always-On is enabled and the Connect Failure Policy is open, the following message is displayed on each connection attempt:. The end user must perform captive portal remediation by meeting the requirements of the provider of the hotspot.
These requirements could be paying a fee to access the network, signing an acceptable use policy, both, or some other requirement defined by the provider. If Always-On is enabled and the connect failure policy is closed, captive portal remediation needs to be explicitly enabled.
If enabled, the end user can perform remediation as described above. If disabled, the following message is displayed upon each connection attempt, and the VPN cannot be connected. You configure captive portal remediation only when the Always-On feature is enabled and the Connect Failure Policy is set to closed.
In this situation, configuring captive portal remediation allows AnyConnect to connect to the VPN when a captive portal is preventing it from doing so. If the Connect Failure Policy is set to open or Always-On is not enabled, your users are not restricted from network access and are capable of remediating a captive portal without any specific configuration in the AnyConnect VPN client profile.
By default, captive portal remediation is disabled on platforms supporting Always on Windows and macOS to provide the greatest security. AnyConnect does not provide data leakage protection capabilities during the captive portal remediation phase.
If data loss protection is desired, you should employ a relevant endpoint security product. Select Allow Captive Portal Remediation. This setting lifts the network access restrictions imposed by the closed connect failure policy. Enter the number of minutes for which AnyConnect lifts the network access restrictions. The user needs enough time to satisfy the captive portal requirements. AnyConnect can falsely assume that it is in a captive portal in the following situations.
To prevent this, make sure the ASA certificate is properly configured. This situation can occur when a user is on an internal network, and connects through a firewall to connect to the ASA. If users cannot access a captive portal remediation page, ask them to try the following:. Terminate any applications that use HTTP, such as instant messaging programs, e-mail clients, IP phone clients, and all but one browser to perform the remediation.
The captive portal may be actively inhibiting DoS attacks by ignoring repetitive attempts to connect, causing them to time out on the client end. The attempt by many applications to make HTTP connections exacerbates this problem. Disable and re-enable the network interface. This action triggers a captive portal detection retry.
To send traffic destined for the secure gateway over a Point-to-Point Protocol PPP connection, AnyConnect uses the point-to-point adapter generated by the external tunnel. Choose a PPP Exclusion method. Also, check User Controllable for this field to let users view and change this setting:.
Automatic—Enables PPP exclusion. If automatic detection does not work and you configured the PPP Exclusion fields as user controllable, the user can override the setting by editing the AnyConnect preferences file on the local computer. Use an editor such as Notepad to open the preferences XML file.
For example,. The address must be a well-formed IPv4 address. For example:. A local proxy runs on the same PC as AnyConnect, and is sometimes used as a transparent proxy. Some examples of a transparent proxy service include acceleration software provided by some wireless data cards, or a network component on some antivirus software, such as Kaspersky. Public proxies are usually used to anonymize web traffic. When Windows is configured to use a public proxy, AnyConnect uses that connection.
Public proxy is supported on macOS and Linux for both native and override. Private proxy servers are used on a corporate network to prevent corporate users from accessing certain Web sites based on corporate usage policies, for example, pornography, gambling, or gaming sites.
You configure a group policy to download private proxy settings to the browser after the tunnel is established. The settings return to their original state after the VPN session ends. See Configure a Private Proxy Connection. AnyConnect SBL connections through a proxy server are dependent on the Windows operating system version and system machine configuration or other third-party proxy software capabilities; therefore, refer to system wide proxy settings as provided by Microsoft or whatever third-party proxy application you use.
The VPN Client profile can block or redirect the client system's proxy connection. For Windows and Linux, you can configure, or you can allow the user to configure, the address of a public proxy server. Some versions of the ASA require AnyConnect configuration to support clientless portal access through a proxy server after establishing an AnyConnect session.
AnyConnect uses a proxy auto-configuration PAC file to modify the client-side proxy settings to let this occur. AnyConnect generates this file only if the ASA does not specify private-side proxy settings. OS support of proxy connections varies as shown:. IPv6 proxies are not supported for any type of proxy connection.
Connecting through a proxy is not supported with the Always-On feature enabled. Select default or unselect Allow Local Proxy Connections. Local proxy is disabled by default.
Configure the private proxy information in the ASA group policy. In a macOS environment, the proxy information that is pushed down from the ASA upon a VPN connection is not viewed in the browser until you open up a terminal and issue a scutil --proxy.
This prevents the user from establishing a tunnel from outside the corporate network, and prevents AnyConnect from connecting through an undesirable or illegitimate proxy server. In the Proxy Settings drop-down list, choose IgnoreProxy. Ignore Proxy causes the client to ignore all proxy settings. No action is taken against proxies that are downloaded from the ASA.
When exposed, this tab lets the user set proxy information. Hiding this tab prevents the user from intentionally or unintentionally circumventing the tunnel. The tab lockdown is reversed on disconnect, and it is superseded by any administrator-defined policies applied to that tab.
The conditions under which this lock down occurs are the following:. The ASA configuration specifies Connections tab lockdown. The ASA configuration specifies a private-side proxy. A Windows group policy previously locked down the Connections tab overriding the no lockdown ASA group policy setting.
You can configure the ASA to allow or not allow proxy lockdown, in the group policy. To do this using ASDM, follow this procedure:. The Proxy Server Policy pane displays. Click Proxy Lockdown to display more proxy settings. Uncheck Inherit and select Yes to enable proxy lockdown and hide the Internet Explorer Connections tab for the duration of the AnyConnect session or; select No to disable proxy lockdown and expose the Internet Explorer Connections tab for the duration of the AnyConnect session.
Click Apply to save the Group Policy changes. For Windows: Find the proxy settings in the registry under:. If Client Bypass Protocol is enabled for an IP protocol and an address pool is not configured for that protocol in other words, no IP address for that protocol was assigned to client by the ASA , any IP traffic using that protocol will not be sent through the VPN tunnel.
It will be sent outside the tunnel. If Client Bypass Protocol is disabled, and an address pool is not configured for that protocol, the client drops all traffic for that IP protocol once the VPN tunnel is established. Next to Client Bypass Protocol , uncheck Inherit if this is a group policy other than the default group policy.
Click Enable to send that IP traffic in the clear. Click Apply. PTR queries matching any of the tunneled networks are allowed through the tunnel.
To configure split DNS for split include tunneling in the group policy, do the following:. If they do, name resolution may not function properly. For example, you can use a ping or web browser to test the split DNS solution.
To use the client to check which domains are used for split DNS, follow these steps:. Those extra domains added after establishing the tunnel are the domains used for split DNS. This process assumes that the domains pushed from the ASA do not overlap with the ones already configured on the client host. The AnyConnect client does not support certificate verification using certificate revocation lists CRL.
Many sites position the Certificate Authority they use to validate server certificates inside the corporate network. That means that a client cannot verify CRL when it is trying to connect to a headend, since the CRL is not accessible on the public network.
When enabled in the profile editor, AnyConnect retrieves the updated CRL for all certificates in the chain. It then verifies whether the certificate in question is among those revoked certificates which should no longer be trusted; and if found to be a certificate revoked by the Certificate Authority, it does not connect. Refer to Local Policy Preferences for further information. When a user connects to an ASA that is configured with a server certificate, the checkbox to trust and import that certificate will still display, even if there is a problem with the trust chain Root, Intermediate, etc.
If there are any other certificate problems, that checkbox will not display. IPsec and SSL connections perform name verification on server certificates. If a Subject Alternative Name extension is present with relevant attributes, name verification is performed solely against the Subject Alternative Name.
Relevant attributes include DNS Name attributes for all certificates, and additionally include IP address attributes if the connection is being performed to an IP address. If a Subject Alternative Name extension is not present, or is present but contains no relevant attributes, name verification is performed against any Common Name attributes found in the Subject of the certificate.
If a certificate uses a wildcard for the purposes of name verification, the wildcard must be in the first left-most subdomain only, and additionally must be the last right-most character in the subdomain.
Any wildcard entry not in compliance is ignored for the purposes of name verification. In response to the increase of targeted attacks against mobile users on untrusted networks, we have improved the security protections in the client to help prevent serious security breaches.
The default client behavior has been changed to provide an extra layer of defense against Man-in-the-middle attacks. When the user tries to connect to a secure gateway, and there is a certificate error due to expired, invalid date, wrong key usage, or CN mismatch , the user sees a red-colored dialog with Change Settings and Keep Me Safe buttons.
The dialogs for Linux may look different from the ones shown in this document. Clicking Keep Me Safe cancels the connection. The current connection attempt is canceled. If the user un-checks Block connections to untrusted servers , and the only issue with the certificate is that the CA is untrusted, then the next time the user attempts to connect to this secure gateway, the user will not see the Certificate Blocked Error Dialog dialog; they only see the following dialog:.
If the user checks Always trust this VPN server and import the certificate , then future connections to this secure gateway will not prompt the user to continue.
When the client accepts an invalid server certificate, that certificate is saved in the client's certificate store. Previously, only the thumbprint of the certificate was saved. Note that invalid certificates are saved only when the user has elected to always trust and import invalid server certificates. There is no administrative override to make the end user less secure automatically. When Strict Certificate Trust is enabled, the user sees an error message, and the connection fails; there is no user prompt.
AnyConnect is configured to start before logon. A client certificate from the machine certificate store is used for authentication. You can specify whether you want users to authenticate using AAA with a username and password or using a digital certificate or both. When you configure certificate-only authentication, users can connect with a digital certificate and are not required to provide a user ID and password.
To support certificate-only authentication in an environment where multiple groups are used, you may provision more than one group-url. Each group-url would contain a different client profile with some piece of customized data that would allow for a group-specific certificate map to be created.
The certificate used to authenticate the client to the secure gateway must be valid and trusted signed by a CA. A self-signed client certificate will not be accepted. Select a connection profile and click Edit. If it is not already, click the Basic node of the navigation tree on the left pane of the window.
In the right pane of the window, in the Authentication area, enable the method Certificate. Click OK and apply your changes. Enrollment is always initiated automatically by the client.
No user involvement is necessary. Enrollment is initiated automatically by the client and may be initiated manually by the user if configured. The user connects to the ASA headend using a connection profile configured for both certificate and AAA authentication. This situation triggers the client to send an automatic SCEP enrollment request after the tunnel has been established using the entered AAA credentials.
If SCEP enrollment is successful, the client presents a configurable message to the user and disconnects the current session. The user can now connect using certificate authentication to an ASA tunnel group. If SCEP enrollment fails, the client displays a configurable message to the user and disconnects the current session.
If configured to do so, the client automatically renews the certificate before it expires, without user intervention. The following steps describe how a certificate is obtained and a certificate-based connection is made when AnyConnect is configured for Legacy SCEP.
When the user initiates a connection to the ASA headend using a tunnel group configured for certificate authentication, the ASA requests a certificate for authentication from the client.
A valid certificate is not available on the client. The connection cannot be established. This certificate failure indicates that SCEP enrollment needs to occur. The client presents a dialog box for the user to enter AAA credentials.
If access to the CA relies on the VPN tunnel being established, manual enrollment cannot be done at this time because there is currently no VPN tunnel established AAA credentials have not been entered. If the client is configured for manual enrollment and the Certificate Expiration Threshold value is met, a Get Certificate button displays on a presented tunnel group selection dialog box.
Users can manually renew their certificate by clicking this button. If the certificate expires and the client no longer has a valid certificate, the client repeats the Legacy SCEP enrollment process. The CA must be in auto-grant mode; polling for certificates is not supported. You can configure some CAs to email users an enrollment password for an additional layer of security. The CA password is the challenge password or token that is sent to the certificate authority to identify the user.
The password can then be configured in the AnyConnect client profile, which becomes part of SCEP request that the CA verifies before granting the certificate. The ASA does not indicate why an enrollment failed, although it does log the requests received from the client. Connection problems must be debugged on the CA or the client. Identifying Enrollment Connections to Apply Policies:. On the ASA, the aaa. When Windows clients first attempt to retrieve a certificate from a certificate authority they may see a warning.
When prompted, users must click Yes. This allows them to import the root certificate. It does not affect their ability to connect with the client certificate. Select Certificate Enrollment. Configure the Certificate Contents to be requested in the enrollment certificate.
For mobile clients, at least one certificate field must be specified. Set the following fields:. For example, if asa. When the user initiates the connection, the address chosen or specified must match this value exactly for Legacy SCEP enrollment to succeed.
Configure the Certificate Authority attributes:. Optional Enter a thumbprint for the CA certificate. Configure which Certificate Contents to request in the enrollment certificate. Optional Check Display Get Certificate Button to permit users to manually request provisioning or renewal of authentication certificates. The button is visible to users if the certificate authentication fails. Choose Server List from the navigation pane. Add or Edit a server list entry.
Table 1. Unified Endpoint Compliance. Highly Secure Network Access. Administrators can control which networks or resources for endpoints to connect.
It provides an IEEE Web Security. Combining web security with VPN access, administrators can provide comprehensive, highly secure mobility to all end users, which is vital for bring-your-own-device BYOD deployments. Enterprises have a choice of deployments to defend the network against web malware and to control and safeguard web usage. Navigate Windows File Explorer to the installer file.
Double-click Setup. Check your Downloads folder to locate the AnyConnect files. Browser based downloads are often deposited into the downloads folder on your device on windows. A pop-up window may ask for permissions, in this case, select Yes. If your pop-up asks if you are sure you want to run this software, select Run. Enabling this feature will prevent users from disabling the Windows Web Security service.
There you have it!
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