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.

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 flaw was found in the "Leaf and Chain" OCSP policy implementation in JSS' CryptoManager versions after 4.4.6, 4.5.3, 4.6.0, where it implicitly trusted the root certificate of a certificate chain. Applications using this policy may not properly verify the chain and could be vulnerable to attacks such as Man in the Middle.

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.

In the client side of Heimdal before 7.6.0, failure to verify anonymous PKINIT PA-PKINIT-KX key exchange permits a man-in-the-middle attack. This issue is in krb5_init_creds_step in lib/krb5/init_creds_pw.c.

In words.protocols.jabber.xmlstream in Twisted through 19.2.1, XMPP support did not verify certificates when used with TLS, allowing an attacker to MITM 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.

An issue was discovered in ASUSTOR exFAT Driver through 1.0.0.r20. When conducting license validation, exfat.cgi and exfatctl accept any certificate for asustornasapi.asustor.com. In other words, there is Missing SSL Certificate Validation.

Jenkins ElectricFlow Plugin 1.1.5 and earlier disabled SSL/TLS and hostname verification globally for the Jenkins master JVM when MultipartUtility.java is used to upload files.

When TLS is enabled with ssl-endpoint-identification-enabled set to true, Apache Geode fails to perform hostname verification of the entries in the certificate SAN during the SSL handshake. This could compromise intra-cluster communication using a man-in-the-middle attack.

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.

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.

Jenkins VMware Lab Manager Slaves Plugin 0.2.8 and earlier disables SSL/TLS and hostname verification globally for the Jenkins master JVM.

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 vulnerability exists in Jenkins Active Directory Plugin 2.10 and earlier in src/main/java/hudson/plugins/active_directory/ActiveDirectoryDomain.java, src/main/java/hudson/plugins/active_directory/ActiveDirectorySecurityRealm.java, src/main/java/hudson/plugins/active_directory/ActiveDirectoryUnixAuthenticationProvider.java that allows attackers to impersonate the Active Directory server Jenkins connects to for authentication if Jenkins is configured to use StartTLS.

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

Improper certificate validation in Zoom Workplace for Linux before version 6.4.13 may allow an unauthorized user to conduct an information disclosure via network access.

Mifos-Mobile Android Application for MifosX is an Android Application built on top of the MifosX Self-Service platform. Mifos-Mobile before commit e505f62 disables HTTPS hostname verification of its HTTP client. Additionally it accepted any self-signed certificate as valid. Hostname verification is an important part when using HTTPS to ensure that the presented certificate is valid for the host. Disabling it can allow for man-in-the-middle attacks. Accepting any certificate, even self-signed ones allows man-in-the-middle attacks. This problem is fixed in mifos-mobile commit e505f62.

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.

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.

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.

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.

ELECOM WRC-300FEBK-S contains an improper certificate validation vulnerability. Via a man-in-the-middle attack, an attacker may alter the communication response. As a result, an arbitrary OS command may be executed on the affected device.

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.

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.

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.

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.)

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

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

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.

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.

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.

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.

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 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.

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.

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.

WebHybridClient.java in PayPal 5.3 and earlier for Android ignores SSL errors, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information.

The ServerTrustManager component in the Ignite Realtime Smack XMPP API before 4.0.0-rc1 does not verify basicConstraints and nameConstraints in X.509 certificate chains from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate chain.

A man in the middle vulnerability exists in Jenkins Inedo BuildMaster Plugin 1.3 and earlier in BuildMasterConfiguration.java, BuildMasterConfig.java, BuildMasterApi.java that allows attackers to impersonate any service that Jenkins connects to.

A man in the middle vulnerability exists in Jenkins TraceTronic ECU-TEST Plugin 2.3 and earlier in ATXPublisher.java, ATXValidator.java that allows attackers to impersonate any service that Jenkins connects to.

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 Apache Qpid Proton-J transport includes an optional wrapper layer to perform TLS, enabled by use of the 'transport.ssl(...)' methods. Unless a verification mode was explicitly configured, client and server modes previously defaulted as documented to not verifying a peer certificate, with options to configure this explicitly or select a certificate verification mode with or without hostname verification being performed. The latter hostname verifying mode was not implemented in Apache Qpid Proton-J versions 0.3 to 0.29.0, with attempts to use it resulting in an exception. This left only the option to verify the certificate is trusted, leaving such a client vulnerable to Man In The Middle (MITM) attack. Uses of the Proton-J protocol engine which do not utilise the optional transport TLS wrapper are not impacted, e.g. usage within Qpid JMS. Uses of Proton-J utilising the optional transport TLS wrapper layer that wish to enable hostname verification must be upgraded to version 0.30.0 or later and utilise the VerifyMode#VERIFY_PEER_NAME configuration, which is now the default for client mode usage unless configured otherwise.

Dell Networking OS10 versions prior to 10.4.3.0 contain a vulnerability in the Phone Home feature which does not properly validate the server's certificate authority during TLS handshake. Use of an invalid or malicious certificate could potentially allow an attacker to spoof a trusted entity by using 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.

IBM Security Guardium EcoSystem 10.5 does not validate, or incorrectly validates, a certificate.This weakness 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. IBM X-Force ID: 141417.

An Improper Certificate Validation weakness in the Juniper Networks Junos OS allows an attacker to perform Person-in-the-Middle (PitM) attacks when a system script is fetched from a remote source at a specified HTTPS URL, which may compromise the integrity and confidentiality of the device. The following command can be executed by an administrator via the CLI to refresh a script from a remote location, which is affected from this vulnerability: >request system scripts refresh-from (commit | event | extension-service | op | snmp) file filename url <https-url> This issue affects: Juniper Networks Junos OS All versions prior to 18.4R2-S9, 18.4R3-S9; 19.1 versions prior to 19.1R2-S3, 19.1R3-S7; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S7; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R2-S1, 20.3R3; 20.4 versions prior to 20.4R2; 21.1 versions prior to 21.1R1-S1, 21.1R2.

TLS hostname verification when using the Apache ActiveMQ Client before 5.15.6 was missing which could make the client vulnerable to a MITM attack between a Java application using the ActiveMQ client and the ActiveMQ server. This is now enabled by default.