software-properties was vulnerable to a person-in-the-middle attack due to incorrect TLS certificate validation in softwareproperties/ppa.py. software-properties didn't check TLS certificates under python2 and only checked certificates under python3 if a valid certificate bundle was provided. Fixed in software-properties version 0.92.

The SSLVerifySignedServerKeyExchange function in libsecurity_ssl/lib/sslKeyExchange.c in the Secure Transport feature in the Data Security component in Apple iOS 6.x before 6.1.6 and 7.x before 7.0.6, Apple TV 6.x before 6.0.2, and Apple OS X 10.9.x before 10.9.2 does not check the signature in a TLS Server Key Exchange message, which allows man-in-the-middle attackers to spoof SSL servers by (1) using an arbitrary private key for the signing step or (2) omitting the signing step.

The PrinterLogic Print Management software, versions up to and including 18.3.1.96, does not validate, or incorrectly validates, the PrinterLogic management portal's SSL certificate. When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by using a man-in-the-middle (MITM) attack. The software might connect to a malicious host while believing it is a trusted host, or the software might be deceived into accepting spoofed data that appears to originate from a trusted host.

In faye-websocket before version 0.11.0, there is a lack of certification validation in TLS handshakes. The `Faye::WebSocket::Client` class uses the `EM::Connection#start_tls` method in EventMachine to implement the TLS handshake whenever a `wss:` URL is used for the connection. This method does not implement certificate verification by default, meaning that it does not check that the server presents a valid and trusted TLS certificate for the expected hostname. That means that any `wss:` connection made using this library is vulnerable to a man-in-the-middle attack, since it does not confirm the identity of the server it is connected to. For further background information on this issue, please see the referenced GitHub Advisory. Upgrading `faye-websocket` to v0.11.0 is recommended.

OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.

A spoofing vulnerability exists in the way Windows CryptoAPI (Crypt32.dll) validates Elliptic Curve Cryptography (ECC) certificates.An attacker could exploit the vulnerability by using a spoofed code-signing certificate to sign a malicious executable, making it appear the file was from a trusted, legitimate source, aka 'Windows CryptoAPI Spoofing Vulnerability'.

A vulnerability in the Identity Services Engine (ISE) integration feature of Cisco Prime Infrastructure (PI) could allow an unauthenticated, remote attacker to perform a man-in-the-middle attack against the Secure Sockets Layer (SSL) tunnel established between ISE and PI. The vulnerability is due to improper validation of the server SSL certificate when establishing the SSL tunnel with ISE. An attacker could exploit this vulnerability by using a crafted SSL certificate and could then intercept communications between the ISE and PI. A successful exploit could allow the attacker to view and alter potentially sensitive information that the ISE maintains about clients that are connected to the network. This vulnerability affects Cisco Prime Infrastructure Software Releases 2.2 through 3.4.0 when the PI server is integrated with ISE, which is disabled by default.

lib/oauth/consumer.rb in the oauth-ruby gem through 0.5.4 for Ruby does not verify server X.509 certificates if a certificate bundle cannot be found, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information.

A vulnerability was found in keycloak before 6.0.2. The X.509 authenticator supports the verification of client certificates through the CRL, where the CRL list can be obtained from the URL provided in the certificate itself (CDP) or through the separately configured path. The CRL are often available over the network through unsecured protocols ('http' or 'ldap') and hence the caller should verify the signature and possibly the certification path. Keycloak currently doesn't validate signatures on CRL, which can result in a possibility of various attacks like man-in-the-middle.

It was discovered evolution-ews before 3.31.3 does not check the validity of SSL certificates. An attacker could abuse this flaw to get confidential information by tricking the user into connecting to a fake server without the user noticing the difference.

Improper certificate validation in Logstash's TCP output could lead to a man-in-the-middle (MitM) attack in “client” mode, as hostname verification in TCP output was not being performed when the ssl_verification_mode => full was set.

Dell EMC Enterprise Copy Data Management (eCDM) versions 1.0, 1.1, 2.0, 2.1, and 3.0 contain a certificate validation vulnerability. An unauthenticated remote attacker may potentially exploit this vulnerability to carry out a man-in-the-middle attack by supplying a crafted certificate and intercepting the victim's traffic to view or modify a victim’s data in transit.

On versions 15.0.0-15.0.1.1, the BIG-IP ASM Cloud Security Services profile uses a built-in verification mechanism that fails to properly authenticate the X.509 certificate of remote endpoints.

A vulnerability in the Cisco Network Plug-and-Play (PnP) agent of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data. The vulnerability exists because the affected software insufficiently validates certificates. An attacker could exploit this vulnerability by supplying a crafted certificate to an affected device. A successful exploit could allow the attacker to conduct man-in-the-middle attacks to decrypt and modify confidential information on user connections to the affected software.

The Android App 'Tootdon for Mastodon' version 3.4.1 and earlier does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

The NTV News24 prior to Ver.3.0.0 does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

A vulnerability, in The ReportsTrustManager class of Brocade SANnav versions before v2.0, could allow an attacker to perform a man-in-the-middle attack against Secure Sockets Layer(SSL)connections.

A vulnerability in the certificate handling component of the Cisco SPA112, SPA525, and SPA5X5 Series IP Phones could allow an unauthenticated, remote attacker to listen to or control some aspects of a Transport Level Security (TLS)-encrypted Session Initiation Protocol (SIP) conversation. The vulnerability is due to the improper validation of server certificates. An attacker could exploit this vulnerability by crafting a malicious server certificate to present to the client. An exploit could allow an attacker to eavesdrop on TLS-encrypted traffic and potentially route or redirect calls initiated by an affected device. Affected software include version 7.6.2 of the Cisco Small Business SPA525 Series IP Phones and Cisco Small Business SPA5X5 Series IP Phones and version 1.4.2 of the Cisco Small Business SPA500 Series IP Phones and Cisco Small Business SPA112 Series IP Phones.

The Twitter Kit framework through 3.4.2 for iOS does not properly validate the api.twitter.com SSL certificate. Although the certificate chain must contain one of a set of pinned certificates, there are certain implementation errors such as a lack of hostname verification. NOTE: this is an end-of-life product.

IBM QRadar 7.3.0 to 7.3.3 Patch 2 does not validate, or incorrectly validates, a certificate which could allow an attacker to spoof a trusted entity by using a man-in-the-middle (MITM) attack. IBM X-ForceID: 170965.

Savitech driver packages for Windows silently install a self-signed certificate into the Trusted Root Certification Authorities store, aka "Inaudible Subversion."

The mAadhaar application 1.2.7 for Android lacks SSL Certificate Validation, leading to man-in-the-middle attacks against requests for FAQs or Help.

Google Chrome before 18.0.1025.142 does not properly check X.509 certificates before use of a SPDY proxy, which might allow man-in-the-middle attackers to spoof servers or obtain sensitive information via a crafted certificate.

The X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain. It is not set by default. Starting from OpenSSL version 1.1.1h a check to disallow certificates in the chain that have explicitly encoded elliptic curve parameters was added as an additional strict check. An error in the implementation of this check meant that the result of a previous check to confirm that certificates in the chain are valid CA certificates was overwritten. This effectively bypasses the check that non-CA certificates must not be able to issue other certificates. If a "purpose" has been configured then there is a subsequent opportunity for checks that the certificate is a valid CA. All of the named "purpose" values implemented in libcrypto perform this check. Therefore, where a purpose is set the certificate chain will still be rejected even when the strict flag has been used. A purpose is set by default in libssl client and server certificate verification routines, but it can be overridden or removed by an application. In order to be affected, an application must explicitly set the X509_V_FLAG_X509_STRICT verification flag and either not set a purpose for the certificate verification or, in the case of TLS client or server applications, override the default purpose. OpenSSL versions 1.1.1h and newer are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1h-1.1.1j).

It was found that Satellite 5 configured with SSL/TLS for the PostgreSQL backend failed to correctly validate X.509 server certificate host name fields. A man-in-the-middle attacker could use this flaw to spoof a PostgreSQL server using a specially crafted X.509 certificate.

In F5 BIG-IP PEM 12.1.0 through 12.1.2 when downloading the Type Allocation Code (TAC) database file via HTTPS, the server's certificate is not verified. Attackers in a privileged network position may be able to launch a man-in-the-middle attack against these connections. TAC databases are used in BIG-IP PEM for Device Type and OS (DTOS) and Tethering detection. Customers not using BIG-IP PEM, not configuring downloads of TAC database files, or not using HTTP for that download are not affected.

Affected versions of CODESYS Git in Versions prior to V1.1.0.0 lack certificate validation in HTTPS handshakes. CODESYS Git does not implement certificate validation by default, so it does not verify that the server provides a valid and trusted HTTPS certificate. Since the certificate of the server to which the connection is made is not properly verified, the server connection is vulnerable to a man-in-the-middle attack.

The Proofpoint Insider Threat Management Agents (formerly ObserveIT Agent) for MacOS and Linux perform improper validation of the ITM Server's certificate, which enables a remote attacker to intercept and alter these communications using a man-in-the-middle attack. All versions before 7.11.1 are affected. Agents for Windows and Cloud are not affected.

Missing SSL Certificate Validation issue exists in Pluck 4.7.15 in update_applet.php, which could lead to man-in-the-middle attacks.

The AWV component of Mitel MiCollab before 9.3 could allow an attacker to perform a Man-In-the-Middle attack due to improper TLS negotiation. A successful exploit could allow an attacker to view and modify data.

A vulnerability has been identified in SINUMERIK Analyse MyCondition (All versions), SINUMERIK Analyze MyPerformance (All versions), SINUMERIK Analyze MyPerformance /OEE-Monitor (All versions), SINUMERIK Analyze MyPerformance /OEE-Tuning (All versions), SINUMERIK Integrate Client 02 (All versions >= V02.00.12 < 02.00.18), SINUMERIK Integrate Client 03 (All versions >= V03.00.12 < 03.00.18), SINUMERIK Integrate Client 04 (V04.00.02 and all versions >= V04.00.15 < 04.00.18), SINUMERIK Integrate for Production 4.1 (All versions < V4.1 SP10 HF3), SINUMERIK Integrate for Production 5.1 (V5.1), SINUMERIK Manage MyMachines (All versions), SINUMERIK Manage MyMachines /Remote (All versions), SINUMERIK Manage MyMachines /Spindel Monitor (All versions), SINUMERIK Manage MyPrograms (All versions), SINUMERIK Manage MyResources /Programs (All versions), SINUMERIK Manage MyResources /Tools (All versions), SINUMERIK Manage MyTools (All versions), SINUMERIK Operate V4.8 (All versions < V4.8 SP8), SINUMERIK Operate V4.93 (All versions < V4.93 HF7), SINUMERIK Operate V4.94 (All versions < V4.94 HF5), SINUMERIK Optimize MyProgramming /NX-Cam Editor (All versions). Due to an error in a third-party dependency the ssl flags used for setting up a TLS connection to a server are overwitten with wrong settings. This results in a missing validation of the server certificate and thus in a possible TLS MITM szenario.

core/imap/MCIMAPSession.cpp in Canary Mail before 3.22 has Missing SSL Certificate Validation for IMAP in STARTTLS mode.

Apache Sling Commons Messaging Mail provides a simple layer on top of JavaMail/Jakarta Mail for OSGi to send mails via SMTPS. To reduce the risk of "man in the middle" attacks additional server identity checks must be performed when accessing mail servers. For compatibility reasons these additional checks are disabled by default in JavaMail/Jakarta Mail. The SimpleMailService in Apache Sling Commons Messaging Mail 1.0 lacks an option to enable these checks for the shared mail session. A user could enable these checks nevertheless by accessing the session via the message created by SimpleMessageBuilder and setting the property mail.smtps.ssl.checkserveridentity to true. Apache Sling Commons Messaging Mail 2.0 adds support for enabling server identity checks and these checks are enabled by default. - https://javaee.github.io/javamail/docs/SSLNOTES.txt - https://javaee.github.io/javamail/docs/api/com/sun/mail/smtp/package-summary.html - https://github.com/eclipse-ee4j/mail/issues/429

Cerulean Studios Trillian 3.1 Basic does not check SSL certificates during MSN authentication, which allows remote attackers to obtain MSN credentials via a man-in-the-middle attack with a spoofed SSL certificate.

The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2.7.1 does not support a certain special case of a zero name length, which causes silent omission of hostname verification, and consequently allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate. NOTE: the LibreSSL documentation indicates that this special case is supported, but the BoringSSL documentation does not.

An Improper Certificate Validation weakness in the SRX Series Application Identification (app-id) signature update client of Juniper Networks Junos OS allows an attacker to perform Man-in-the-Middle (MitM) attacks which may compromise the integrity and confidentiality of the device. This issue affects: Juniper Networks Junos OS 15.1X49 versions prior to 15.1X49-D120 on SRX Series devices. No other versions of Junos OS are affected.

A vulnerability has been identified in Siveillance VMS Video for Android (All versions < V12.1a (2018 R1)), Siveillance VMS Video for iOS (All versions < V12.1a (2018 R1)). Improper certificate validation could allow an attacker in a privileged network position to read data from and write data to the encrypted communication channel between the app and a server. The security vulnerability could be exploited by an attacker in a privileged network position which allows intercepting the communication channel between the affected app and a server (such as Man-in-the-Middle). Furthermore, an attacker must be able to generate a certificate that results for the validation algorithm in a checksum identical to a trusted certificate. Successful exploitation requires no user interaction. The vulnerability could allow reading data from and writing data to the encrypted communication channel between the app and a server, impacting the communication's confidentiality and integrity. At the time of advisory publication no public exploitation of this security vulnerability was known. Siemens confirms the security vulnerability and provides mitigations to resolve the security issue.

niconico App for iOS before 6.38 does not verify SSL certificates which could allow remote attackers to execute man-in-the-middle attacks.

The Chase mobile banking application for Android does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate, related to overriding the default X509TrustManager. NOTE: this vulnerability was fixed in the summer of 2012, but the version number was not changed or is not known.

ALPACA is an application layer protocol content confusion attack, exploiting TLS servers implementing different protocols but using compatible certificates, such as multi-domain or wildcard certificates. A MiTM attacker having access to victim's traffic at the TCP/IP layer can redirect traffic from one subdomain to another, resulting in a valid TLS session. This breaks the authentication of TLS and cross-protocol attacks may be possible where the behavior of one protocol service may compromise the other at the application layer.

Trillian 5.1.0.19 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate, a different vulnerability than CVE-2009-4831.

Acronis True Image prior to 2021 Update 4 for Windows, Acronis True Image prior to 2021 Update 5 for Mac, Acronis Agent prior to build 26653, Acronis Cyber Protect prior to build 27009 did not implement SSL certificate validation.

Lynx does not verify that the server's certificate is signed by a trusted certification authority, which allows man-in-the-middle attackers to spoof SSL servers via a crafted certificate, related to improper use of a certain GnuTLS function.

Multiple vulnerabilities in Cisco Data Center Network Manager (DCNM) could allow an attacker to spoof a trusted host or construct a man-in-the-middle attack to extract sensitive information or alter certain API requests. These vulnerabilities are due to insufficient certificate validation when establishing HTTPS requests with the affected device. For more information about these vulnerabilities, see the Details section of this advisory.

In versions 3.0.0-3.5.0, 2.0.0-2.9.0, and 1.0.1, when users run the command displayed in NGINX Controller user interface (UI) to fetch the agent installer, the server TLS certificate is not verified.

iSM client versions from V5.1 prior to V12.1 running on NEC Storage Manager or NEC Storage Manager Express does not verify a server certificate properly, which allows a man-in-the-middle attacker to eavesdrop on an encrypted communication or alter the communication via a crafted certificate.

When linking a Nessus scanner or agent to Tenable.io or other manager, Nessus 6.x before 6.11 does not verify the manager's TLS certificate when making the initial outgoing connection. This could allow man-in-the-middle attacks.

VMware vCenter Server (6.7 before 6.7u3, 6.6 before 6.5u3k) contains a session hijack vulnerability in the vCenter Server Appliance Management Interface update function due to a lack of certificate validation. A malicious actor with network positioning between vCenter Server and an update repository may be able to perform a session hijack when the vCenter Server Appliance Management Interface is used to download vCenter updates.

A vulnerability in the SSL implementation of the Cisco Intelligent Proximity solution could allow an unauthenticated, remote attacker to view or alter information shared on Cisco Webex video devices and Cisco collaboration endpoints if the products meet the conditions described in the Vulnerable Products section. The vulnerability is due to a lack of validation of the SSL server certificate received when establishing a connection to a Cisco Webex video device or a Cisco collaboration endpoint. An attacker could exploit this vulnerability by using man in the middle (MITM) techniques to intercept the traffic between the affected client and an endpoint, and then using a forged certificate to impersonate the endpoint. Depending on the configuration of the endpoint, an exploit could allow the attacker to view presentation content shared on it, modify any content being presented by the victim, or have access to call controls. This vulnerability does not affect cloud registered collaboration endpoints.

A TLS certificate validation flaw was found in Elastic APM agent for Ruby versions before 2.9.0. When specifying a trusted server CA certificate via the 'server_ca_cert' setting, the Ruby agent would not properly verify the certificate returned by the APM server. This could result in a man in the middle style attack against the Ruby agent.