Improper Certificate Validation in Checkmk Exchange plugin MikroTik allows attackers in MitM position to intercept traffic. This issue affects MikroTik: from 2.0.0 through 2.5.5, from 0.4a_mk through 2.0a.

Traefik is an HTTP reverse proxy and load balancer. Prior to version 2.6.1, Traefik skips the router transport layer security (TLS) configuration when the host header is a fully qualified domain name (FQDN). For a request, the TLS configuration choice can be different than the router choice, which implies the use of a wrong TLS configuration. When sending a request using FQDN handled by a router configured with a dedicated TLS configuration, the TLS configuration falls back to the default configuration that might not correspond to the configured one. If the CNAME flattening is enabled, the selected TLS configuration is the SNI one and the routing uses the CNAME value, so this can skip the expected TLS configuration. Version 2.6.1 contains a patch for this issue. As a workaround, one may add the FDQN to the host rule. However, there is no workaround if the CNAME flattening is enabled.

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.

An improper certificate validation vulnerability exists in the BIG-IP Edge Client for Windows and macOS and may allow an attacker to impersonate a BIG-IP APM system.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

A vulnerability exists in the component RTU500 Scripting interface. When a client connects to a server using TLS, the server presents a certificate. This certificate links a public key to the identity of the service and is signed by a Certification Authority (CA), allowing the client to validate that the remote service can be trusted and is not malicious. If the client does not validate the parameters of the certificate, then attackers could be able to spoof the identity of the service. An attacker could exploit the vulnerability by using faking the identity of a RTU500 device and intercepting the messages initiated via the RTU500 Scripting interface.

Improper Certificate Validation in GitHub repository pyload/pyload prior to 0.5.0b3.dev44.

Missing validation of server certificates for out-going connections in Nextcloud Social < 0.4.0 allowed a man-in-the-middle attack.

Serverpod is an app and web server, built for the Flutter and Dart ecosystem. This bug bypassed the validation of TSL certificates on all none web HTTP clients in the `serverpod_client` package. Making them susceptible to a man in the middle attack against encrypted traffic between the client device and the server. An attacker would need to be able to intercept the traffic and highjack the connection to the server for this vulnerability to be used. Upgrading to version `1.2.6` resolves this issue.

Android App 'MyPallete' and some of the Android banking applications based on 'MyPallete' do not verify X.509 certificates from servers, and also do not properly validate certificates with host-mismatch, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

A vulnerability exists in the FOXMAN-UN/UNEM server that affects the message queueing mechanism’s certificate validation. If exploited an attacker could spoof a trusted entity causing a loss of confidentiality and integrity.

Due to improper validation of certificate in SAP Cloud Connector - version 2.0, attacker can impersonate the genuine servers to interact with SCC breaking the mutual authentication. Hence, the attacker can intercept the request to view/modify sensitive information. There is no impact on the availability of the system.

A vulnerability has been identified in Industrial Edge Management (All versions < V1.5.1). The affected software does not properly validate the server certificate when initiating a TLS connection. This could allow an attacker to spoof a trusted entity by interfering in the communication path between the client and the intended server.

An improper certificate validation vulnerability [CWE-295] in FortiOS 7.2.0 through 7.2.3, 7.0.0 through 7.0.7, 6.4 all versions, 6.2 all versions, 6.0 all versions and FortiProxy 7.0.0 through 7.0.6, 2.0 all versions, 1.2 all versions may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the FortiOS/FortiProxy device and remote servers hosting threat feeds (when the latter are configured as Fabric connectors in FortiOS/FortiProxy)

When using Ingest Actions to configure a destination that resides on Amazon Simple Storage Service (S3) in Splunk Web, TLS certificate validation is not correctly performed and tested for the destination. The vulnerability only affects connections between Splunk Enterprise and an Ingest Actions Destination through Splunk Web and only applies to environments that have configured TLS certificate validation. It does not apply to Destinations configured directly in the outputs.conf configuration file. The vulnerability affects Splunk Enterprise version 9.0.0 and does not affect versions below 9.0.0, including the 8.1.x and 8.2.x versions.

In Splunk Enterprise and Universal Forwarder versions before 9.0, the Splunk command-line interface (CLI) did not validate TLS certificates while connecting to a remote Splunk platform instance by default. After updating to version 9.0, see Configure TLS host name validation for the Splunk CLI https://docs.splunk.com/Documentation/Splunk/9.0.0/Security/EnableTLSCertHostnameValidation#Configure_TLS_host_name_validation_for_the_Splunk_CLI to enable the remediation. The vulnerability does not affect the Splunk Cloud Platform. At the time of publishing, we have no evidence of exploitation of this vulnerability by external parties. The issue requires conditions beyond the control of a potential bad actor such as a machine-in-the-middle attack. Hence, Splunk rates the complexity of the attack as High.

Accepting arbitrary Subject Alternative Name (SAN) types, unless a PKI is specifically defined to use a particular SAN type, can result in bypassing name-constrained intermediates. Node.js < 12.22.9, < 14.18.3, < 16.13.2, and < 17.3.1 was accepting URI SAN types, which PKIs are often not defined to use. Additionally, when a protocol allows URI SANs, Node.js did not match the URI correctly.Versions of Node.js with the fix for this disable the URI SAN type when checking a certificate against a hostname. This behavior can be reverted through the --security-revert command-line option.

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

e2guardian v5.4.x <= v5.4.3r is affected by missing SSL certificate validation in the SSL MITM engine. In standalone mode (i.e., acting as a proxy or a transparent proxy), with SSL MITM enabled, e2guardian, if built with OpenSSL v1.1.x, did not validate hostnames in certificates of the web servers that it connected to, and thus was itself vulnerable to MITM attacks.

A vulnerability has been discovered in Bitdefender Total Security HTTPS scanning functionality that results in the improper trust of certificates issued using the DSA signature algorithm. The product does not properly check the certificate chain, allowing an attacker to establish MITM SSL connections to arbitrary sites using a DSA-signed certificate.

A vulnerability has been discovered in Bitdefender Total Security HTTPS scanning functionality that results in the improper trust of self-signed certificates. The product is found to trust certificates signed with the RIPEMD-160 hashing algorithm without proper validation, allowing an attacker to establish MITM SSL connections to arbitrary sites.

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 vulnerability has been identified in Bitdefender Total Security HTTPS scanning functionality where the software fails to properly validate website certificates. Specifically, if a site certificate lacks the "Server Authentication" specification in the Extended Key Usage extension, the product does not verify the certificate's compliance with the site, deeming such certificates as valid. This flaw could allow an attacker to perform a Man-in-the-Middle (MITM) attack, intercepting and potentially altering communications between the user and the website.

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).

A flaw was found in the python-scciclient when making an HTTPS connection to a server where the server's certificate would not be verified. This issue opens up the connection to possible Man-in-the-middle (MITM) attacks.

An improper certificate validation vulnerability [CWE-295] in FortiADC 7.4.0, 7.2.0 through 7.2.3, 7.1 all versions, 7.0 all versions, 6.2 all versions, 6.1 all versions and 6.0 all versions may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the device and various remote servers such as private SDN connectors and FortiToken Cloud.

A vulnerability has been identified in Bitdefender Total Security HTTPS scanning functionality where the software trusts a certificate issued by an entity that isn't authorized to issue certificates. This occurs when the "Basic Constraints" extension in the certificate indicates that it is meant to be an "End Entity”. This flaw could allow an attacker to perform a Man-in-the-Middle (MITM) attack, intercepting and potentially altering communications between the user and the website.

Missing SSL certificate validation in localstack v2.3.2 allows attackers to eavesdrop on communications between the host and server via a man-in-the-middle attack.

WP-CLI is the command-line interface for WordPress. An improper error handling in HTTPS requests management in WP-CLI version 0.12.0 and later allows remote attackers able to intercept the communication to remotely disable the certificate verification on WP-CLI side, gaining full control over the communication content, including the ability to impersonate update servers and push malicious updates towards WordPress instances controlled by the vulnerable WP-CLI agent, or push malicious updates toward WP-CLI itself. The vulnerability stems from the fact that the default behavior of `WP_CLI\Utils\http_request()` when encountering a TLS handshake error is to disable certificate validation and retry the same request. The default behavior has been changed with version 2.5.0 of WP-CLI and the `wp-cli/wp-cli` framework (via https://github.com/wp-cli/wp-cli/pull/5523) so that the `WP_CLI\Utils\http_request()` method accepts an `$insecure` option that is `false` by default and consequently that a TLS handshake failure is a hard error by default. This new default is a breaking change and ripples through to all consumers of `WP_CLI\Utils\http_request()`, including those in separate WP-CLI bundled or third-party packages. https://github.com/wp-cli/wp-cli/pull/5523 has also added an `--insecure` flag to the `cli update` command to counter this breaking change. There is no direct workaround for the default insecure behavior of `wp-cli/wp-cli` versions before 2.5.0. The workaround for dealing with the breaking change in the commands directly affected by the new secure default behavior is to add the `--insecure` flag to manually opt-in to the previous insecure behavior.

An improper certificate validation issue in Smartcard authentication in GitLab EE affecting all versions from 11.6 prior to 16.4.4, 16.5 prior to 16.5.4, and 16.6 prior to 16.6.2 allows an attacker to authenticate as another user given their public key if they use Smartcard authentication. Smartcard authentication is an experimental feature and has to be manually enabled by an administrator.

Codehaus XFire 1.2.6 and earlier, as used in the Amazon EC2 API Tools Java library and other products, 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.

em-imap 0.5 uses the library eventmachine in an insecure way that allows an attacker to perform a man-in-the-middle attack against users of the library. The hostname in a TLS server certificate is not verified.

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

EM-HTTP-Request 1.1.5 uses the library eventmachine in an insecure way that allows an attacker to perform a man-in-the-middle attack against users of the library. The hostname in a TLS server certificate is not verified.

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.

A vulnerability was found in the Hot Rod client. This security issue occurs as the Hot Rod client does not enable hostname validation when using TLS, possibly resulting in a man-in-the-middle (MITM) attack.

It was discovered that the sls-logging was not verifying hostnames in TLS certificates due to a misuse of the javax.net.ssl.SSLSocketFactory API. A malicious attacker in a privileged network position could abuse this to perform a man-in-the-middle attack. A successful man-in-the-middle attack would allow them to intercept, read, or modify network communications to and from the affected service. In the case of AtlasDB, the vulnerability was mitigated by other network controls such as two-way TLS when deployed as part of a Palantir platform. Palantir still recommends upgrading to a non-vulnerable version out of an abundance of caution.

The SNKRDUNK Market Place App for iOS versions prior to 2.2.0 does not verify server certificate properly, which allows man-in-the-middle attackers to eavesdrop on and/or alter encrypted communication via a crafted certificate.

Dell EMC Unisphere for PowerMax versions before 9.1.0.27, Dell EMC Unisphere for PowerMax Virtual Appliance versions before 9.1.0.27, and PowerMax OS Release 5978 contain an improper 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.

Open Build Service before version 0.165.4 diddn't validate TLS certificates for HTTPS connections with the osc client binary

The httplib and urllib Python libraries that Splunk shipped with Splunk Enterprise did not validate certificates using the certificate authority (CA) certificate stores by default in Splunk Enterprise versions before 9.0 and Splunk Cloud Platform versions before 8.2.2203. Python 3 client libraries now verify server certificates by default and use the appropriate CA certificate stores for each library. Apps and add-ons that include their own HTTP libraries are not affected. For Splunk Enterprise, update to Splunk Enterprise version 9.0 and Configure TLS host name validation for Splunk-to-Splunk communications (https://docs.splunk.com/Documentation/Splunk/9.0.0/Security/EnableTLSCertHostnameValidation) to enable the remediation.

A vulnerability in the Cisco Identity Services Engine (ISE) integration feature of the Cisco DNA Center Software could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data. The vulnerability is due to an incomplete validation of the X.509 certificate used when establishing a connection between DNA Center and an ISE server. An attacker could exploit this vulnerability by supplying a crafted certificate and could then intercept communications between the ISE and DNA Center. A successful exploit could allow the attacker to view and alter sensitive information that the ISE maintains about clients that are connected to the network.

A vulnerability in the Cisco Advanced Malware Protection (AMP) for Endpoints integration of Cisco AsyncOS for Cisco Email Security Appliance (ESA) and Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to intercept traffic between an affected device and the AMP servers. This vulnerability is due to improper certificate validation when an affected device establishes TLS connections. A man-in-the-middle attacker could exploit this vulnerability by sending a crafted TLS packet to an affected device. A successful exploit could allow the attacker to spoof a trusted host and then extract sensitive information or alter certain API requests.

TLS session reuse can lead to host certificate verification bypass in node version < 12.18.0 and < 14.4.0.

The contribution feature in Zamboni 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 use of the Python urllib2 library.

Avast AntiTrack before 1.5.1.172 and AVG Antitrack before 2.0.0.178 proxies traffic to HTTPS sites but does not validate certificates, and thus a man-in-the-middle can host a malicious website using a self-signed certificate. No special action necessary by the victim using AntiTrack with "Allow filtering of HTTPS traffic for tracking detection" enabled. (This is the default configuration.)

FilesAnywhere 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.

In JetBrains IntelliJ IDEA before 2019.3, some Maven repositories were accessed via HTTP instead of HTTPS.

Improper certificate validation for certain connections in the Bosch Smart Home System App for iOS prior to version 9.17.1 potentially allows to intercept video contents by performing a man-in-the-middle attack.

The netprint App for iOS 3.2.3 and earlier does not verify X.509 certificates from servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

In versions 15.0.0-15.1.0.1, 14.1.0-14.1.2.3, 13.1.0-13.1.3.4, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.2, the BIG-IP Client or Server SSL profile ignores revoked certificates, even when a valid CRL is present. This impacts SSL/TLS connections and may result in a man-in-the-middle attack on the connections.