VPN vulnerabilities

A vulnerability in the Locator ID Separation Protocol (LISP) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to the incorrect handling of LISP packets. An attacker could exploit this vulnerability by sending a crafted LISP packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Note: This vulnerability could be exploited over either IPv4 or IPv6 transport.

A vulnerability in auxiliary asynchronous port (AUX) functions of Cisco IOS XE Software could allow an authenticated, local attacker to cause an affected device to reload or stop responding. This vulnerability is due to the incorrect handling of specific ingress traffic when flow control hardware is enabled on the AUX port. An attacker could exploit this vulnerability by reverse telnetting to the AUX port and sending specific data after connecting. A successful exploit could allow the attacker to cause the device to reset or stop responding, resulting in a denial of service (DoS) condition.

A vulnerability in the Unified Threat Defense (UTD) configuration CLI of Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary commands as root on the underlying host operating system. To exploit this vulnerability, an attacker must have level 15 privileges on the affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by submitting a crafted CLI command to an affected device. A successful exploit could allow the attacker to execute arbitrary commands as root on the underlying operating system.

A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management of mDNS client entries. An attacker could exploit this vulnerability by connecting to the wireless network and sending a continuous stream of specific mDNS packets. A successful exploit could allow the attacker to cause the wireless controller to have high CPU utilization, which could lead to access points (APs) losing their connection to the controller and result in a DoS condition.

A vulnerability in the NETCONF feature of Cisco IOS XE Software could allow an authenticated, remote attacker to elevate privileges to root on an affected device. This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending crafted input over NETCONF to an affected device. A successful exploit could allow the attacker to elevate privileges from Administrator to root.

A vulnerability in Cisco IOS Software for Cisco Catalyst 6000 Series Switches could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly. This vulnerability is due to improper handling of process-switched traffic. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the IP packet processing of Cisco Access Point (AP) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of certain IPv4 packets. An attacker could exploit this vulnerability by sending a crafted IPv4 packet either to or through an affected device. A successful exploit could allow the attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition. To successfully exploit this vulnerability, the attacker does not need to be associated with the affected AP. This vulnerability cannot be exploited by sending IPv6 packets.

A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to a crafted IPv4 DHCP request packet being mishandled when endpoint analytics are enabled. An attacker could exploit this vulnerability by sending a crafted DHCP request through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: The attack vector is listed as network because a DHCP relay anywhere on the network could allow exploits from networks other than the adjacent one.

An authorization bypass through user-controlled key vulnerability [CWE-639] in FortiOS version 7.4.0 through 7.4.1, 7.2.0 through 7.2.6, 7.0.1 through 7.0.13, 6.4.7 through 6.4.14, and FortiProxy version 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14 SSL-VPN may allow an authenticated attacker to gain access to another user’s bookmark via URL manipulation.

A stack-based buffer overflow vulnerability in Fortinet FortiOS 7.4.0 through 7.4.1, FortiOS 7.2.0 through 7.2.5, FortiOS 7.0.0 through 7.0.12, FortiOS 6.4.0 through 6.4.14, FortiOS 6.2.0 through 6.2.15, FortiProxy 7.4.0, FortiProxy 7.2.0 through 7.2.6, FortiProxy 7.0.0 through 7.0.12, FortiProxy 2.0.0 through 2.0.13, FortiSASE 23.2.b allows attacker to execute unauthorized code or commands via specially crafted HTTP requests.

A out-of-bounds write vulnerability in Fortinet FortiOS 7.4.0 through 7.4.1, FortiOS 7.2.0 through 7.2.5, FortiOS 7.0.0 through 7.0.12, FortiOS 6.4.0 through 6.4.14, FortiOS 6.2.0 through 6.2.15, FortiProxy 7.4.0, FortiProxy 7.2.0 through 7.2.6, FortiProxy 7.0.0 through 7.0.12, FortiProxy 2.0.0 through 2.0.13, FortiSASE 23.2.b allows attacker to execute unauthorized code or commands via specially crafted HTTP requests.

A vulnerability in the ISE Posture (System Scan) module of Cisco Secure Client for Linux could allow an authenticated, local attacker to elevate privileges on an affected device. This vulnerability is due to the use of an uncontrolled search path element. An attacker could exploit this vulnerability by copying a malicious library file to a specific directory in the filesystem and persuading an administrator to restart a specific process. A successful exploit could allow the attacker to execute arbitrary code on an affected device with root privileges.

A vulnerability in the SAML authentication process of Cisco Secure Client could allow an unauthenticated, remote attacker to conduct a carriage return line feed (CRLF) injection attack against a user. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by persuading a user to click a crafted link while establishing a VPN session. A successful exploit could allow the attacker to execute arbitrary script code in the browser or access sensitive, browser-based information, including a valid SAML token. The attacker could then use the token to establish a remote access VPN session with the privileges of the affected user. Individual hosts and services behind the VPN headend would still need additional credentials for successful access.

An integer underflow vulnerability exists in the sopen_FAMOS_read functionality of The Biosig Project libbiosig 2.5.0 and Master Branch (ab0ee111). A specially crafted .famos file can lead to an out-of-bounds write which in turn can lead to arbitrary code execution. An attacker can provide a malicious file to trigger this vulnerability.

The nodejs framework in OpenVPN Connect 3.0 through 3.4.3 (Windows)/3.4.7 (macOS) was not properly configured, which allows a local user to execute arbitrary code within the nodejs process context via the ELECTRON_RUN_AS_NODE environment variable

A use of externally-controlled format string in Fortinet FortiOS versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, FortiProxy versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14, FortiPAM versions 1.2.0, 1.1.0 through 1.1.2, 1.0.0 through 1.0.3, FortiSwitchManager versions 7.2.0 through 7.2.3, 7.0.0 through 7.0.3 allows attacker to execute unauthorized code or commands via specially crafted packets.

An improper certificate validation vulnerability in Fortinet FortiOS 7.4.0 through 7.4.1, FortiOS 7.2.0 through 7.2.6, FortiOS 7.0.0 through 7.0.15, FortiOS 6.4 all versions allows a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the FortiLink communication channel between the FortiOS device and FortiSwitch.

An XML external entity or XXE vulnerability in the SAML component of Ivanti Connect Secure (9.x, 22.x), Ivanti Policy Secure (9.x, 22.x) and ZTA gateways which allows an attacker to access certain restricted resources without authentication.

A out-of-bounds write in Fortinet FortiOS versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, 6.0.0 through 6.0.17, FortiProxy versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14, 2.0.0 through 2.0.13, 1.2.0 through 1.2.13, 1.1.0 through 1.1.6, 1.0.0 through 1.0.7 allows attacker to execute unauthorized code or commands via specifically crafted requests

An improper authentication vulnerability has been identified in SonicWall SonicOS SSL-VPN feature, which in specific conditions could allow a remote attacker to bypass authentication.  This issue affects only firmware version SonicOS 7.1.1-7040.

A server-side request forgery vulnerability in the SAML component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) and Ivanti Neurons for ZTA allows an attacker to access certain restricted resources without authentication.

A privilege escalation vulnerability in web component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) allows a user to elevate privileges to that of an administrator.

Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read

Improper Control of Generation of Code ('Code Injection') in NetScaler ADC and NetScaler Gateway allows an attacker with access to NSIP, CLIP or SNIP with management interface to perform Authenticated (low privileged) remote code execution on Management Interface.

A command injection vulnerability in web components of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) allows an authenticated administrator to send specially crafted requests and execute arbitrary commands on the appliance.

An authentication bypass vulnerability in the web component of Ivanti ICS 9.x, 22.x and Ivanti Policy Secure allows a remote attacker to access restricted resources by bypassing control checks.

A vulnerability exists on all versions of Ivanti Connect Secure below 22.6R2 where an attacker can send a specific request which may lead to Denial of Service (DoS) of the appliance.

A vulnerability exists on all versions of Ivanti Connect Secure below 22.6R2 where an attacker with a foothold on an Ivanti Connect Secure (ICS) appliance can escalate their privileges by exploiting a vulnerable installed application. This vulnerability allows the attacker to gain elevated execution privileges on the affected system.

Improper neutralization of special elements in the SMA100 SSL-VPN management interface allows a remote authenticated attacker with administrative privilege to inject arbitrary commands as a 'nobody' user, potentially leading to OS Command Injection Vulnerability.

Multiple vulnerabilities in Cisco Secure Client Software, formerly AnyConnect Secure Mobility Client, could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. These vulnerabilities are due to an out-of-bounds memory read from Cisco Secure Client Software. An attacker could exploit these vulnerabilities by logging in to an affected device at the same time that another user is accessing Cisco Secure Client on the same system, and then sending crafted packets to a port on that local host. A successful exploit could allow the attacker to crash the VPN Agent service, causing it to be unavailable to all users of the system. To exploit these vulnerabilities, the attacker must have valid credentials on a multi-user system.

Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.

Using the --fragment option in certain configuration setups OpenVPN version 2.6.0 to 2.6.6 allows an attacker to trigger a divide by zero behaviour which could cause an application crash, leading to a denial of service.

Multiple Cisco products are affected by a vulnerability in Snort access control policies that could allow an unauthenticated, remote attacker to bypass the configured policies on an affected system. This vulnerability is due to a logic error that occurs when the access control policies are being populated. An attacker could exploit this vulnerability by establishing a connection to an affected device. A successful exploit could allow the attacker to bypass configured access control rules on the affected system.

A vulnerability in the AnyConnect SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an implementation error within the SSL/TLS session handling process that can prevent the release of a session handler under specific conditions. An attacker could exploit this vulnerability by sending crafted SSL/TLS traffic to an affected device, increasing the probability of session handler leaks. A successful exploit could allow the attacker to eventually deplete the available session handler pool, preventing new sessions from being established and causing a DoS condition.

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an authenticated, remote attacker to inject commands with the privileges of root. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted input to the web UI. A successful exploit could allow the attacker to inject commands to the underlying operating system with root privileges.

Cisco is providing an update for the ongoing investigation into observed exploitation of the web UI feature in Cisco IOS XE Software. We are updating the list of fixed releases and adding the Software Checker. Our investigation has determined that the actors exploited two previously unknown issues. The attacker first exploited CVE-2023-20198 to gain initial access and issued a privilege 15 command to create a local user and password combination. This allowed the user to log in with normal user access. The attacker then exploited another component of the web UI feature, leveraging the new local user to elevate privilege to root and write the implant to the file system. Cisco has assigned CVE-2023-20273 to this issue. CVE-2023-20198 has been assigned a CVSS Score of 10.0. CVE-2023-20273 has been assigned a CVSS Score of 7.2. Both of these CVEs are being tracked by CSCwh87343.

An authentication bypass vulnerability exists in the CiRpcAccepted() functionality of SoftEther VPN 4.41-9782-beta and 5.01.9674. A specially crafted network packet can lead to unauthorized access. An attacker can send a network request to trigger this vulnerability.

A heap-based buffer overflow vulnerability exists in the vpnserver WpcParsePacket() functionality of SoftEther VPN 4.41-9782-beta, 5.01.9674 and 5.02. A specially crafted network packet can lead to arbitrary code execution. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.

An authentication bypass vulnerability exists in the CiRpcServerThread() functionality of SoftEther VPN 5.01.9674 and 4.41-9782-beta. An attacker can perform a local man-in-the-middle attack to trigger this vulnerability.

An information disclosure vulnerability exists in the CtEnumCa() functionality of SoftEther VPN 4.41-9782-beta and 5.01.9674. Specially crafted network packets can lead to a disclosure of sensitive information. An attacker can send packets to trigger this vulnerability.

An information disclosure vulnerability exists in the ClientConnect() functionality of SoftEther VPN 5.01.9674. A specially crafted network packet can lead to a disclosure of sensitive information. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.

A denial-of-service vulnerability exists in the vpnserver ConnectionAccept() functionality of SoftEther VPN 5.02. A set of specially crafted network connections can lead to denial of service. An attacker can send a sequence of malicious packets to trigger this vulnerability.

A denial-of-service vulnerability exists in the vpnserver EnSafeHttpHeaderValueStr functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service.

A denial of service vulnerability exists in the DCRegister DDNS_RPC_MAX_RECV_SIZE functionality of SoftEther VPN 4.41-9782-beta, 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.

An integer underflow vulnerability exists in the vpnserver OvsProcessData functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service. An attacker can send a malicious packet to trigger this vulnerability.

Sensitive information disclosure in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA  virtual server.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. This vulnerability is due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols of the GET VPN feature. An attacker could exploit this vulnerability by either compromising an installed key server or modifying the configuration of a group member to point to a key server that is controlled by the attacker. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a denial of service (DoS) condition. For more information, see the Details ["#details"] section of this advisory.

A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or an authenticated, remote attacker to establish a clientless SSL VPN session with an unauthorized user. This vulnerability is due to improper separation of authentication, authorization, and accounting (AAA) between the remote access VPN feature and the HTTPS management and site-to-site VPN features. An attacker could exploit this vulnerability by specifying a default connection profile/tunnel group while conducting a brute force attack or while establishing a clientless SSL VPN session using valid credentials. A successful exploit could allow the attacker to achieve one or both of the following: Identify valid credentials that could then be used to establish an unauthorized remote access VPN session. Establish a clientless SSL VPN session (only when running Cisco ASA Software Release 9.16 or earlier). Notes: Establishing a client-based remote access VPN tunnel is not possible as these default connection profiles/tunnel groups do not and cannot have an IP address pool configured. This vulnerability does not allow an attacker to bypass authentication. To successfully establish a remote access VPN session, valid credentials are required, including a valid second factor if multi-factor authentication (MFA) is configured. Cisco will release software updates that address this vulnerability. There are workarounds that address this vulnerability.

Control Channel in OpenVPN 2.4.7 and earlier allows remote attackers to cause a denial of service via crafted reset packet.