Pivotal Cloud Foundry 239 and earlier, UAA (aka User Account and Authentication Server) 3.4.1 and earlier, UAA release 12.2 and earlier, PCF (aka Pivotal Cloud Foundry) Elastic Runtime 1.6.x before 1.6.35, and PCF Elastic Runtime 1.7.x before 1.7.13 does not validate if a certificate is expired.

The C client and C-based client bindings in the Apache Qpid Proton library before 0.13.1 on Windows do not properly verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate when using the SChannel-based security layer, which allows man-in-the-middle attackers to spoof servers via an arbitrary valid certificate.

The apt package in Debian jessie before 1.0.9.8.4, in Debian unstable before 1.4~beta2, in Ubuntu 14.04 LTS before 1.0.1ubuntu2.17, in Ubuntu 16.04 LTS before 1.2.15ubuntu0.2, and in Ubuntu 16.10 before 1.3.2ubuntu0.1 allows man-in-the-middle attackers to bypass a repository-signing protection mechanism by leveraging improper error handling when validating InRelease file signatures.

Tokyo Star bank App for Android before 1.4 and Tokyo Star bank App for iOS before 1.4 do not validate SSL certificates.

The com.softphone.common package in the Grandstream Wave app 1.0.1.26 and earlier for Android does not properly validate SSL certificates, which allows man-in-the-middle attackers to spoof the Grandstream provisioning server via a crafted certificate.

electron-packager is a command line tool that packages Electron source code into `.app` and `.exe` packages. along with Electron. The `--strict-ssl` command line option in electron-packager >= 5.2.1 <= 6.0.0 || >=6.0.0 <= 6.0.2 defaults to false if not explicitly set to true. This could allow an attacker to perform a man in the middle attack.

Apache Tomcat Native 1.2.0 to 1.2.16 and 1.1.23 to 1.1.34 has a flaw that does not properly check OCSP pre-produced responses, which are lists (multiple entries) of certificate statuses. Subsequently, revoked client certificates may not be properly identified, allowing for users to authenticate with revoked certificates to connections that require mutual TLS. Users not using OCSP checks are not affected by this vulnerability.

An issue was discovered in certain Apple products. iOS before 11.2.5 is affected. macOS before 10.13.3 is affected. tvOS before 11.2.5 is affected. watchOS before 4.2.2 is affected. The issue involves the "Security" component. It allows remote attackers to spoof certificate validation via crafted name constraints.

On 2N Access Unit 2.0 2.31.0.40.5 devices, an attacker can pose as the web relay for a man-in-the-middle attack.

HashiCorp Vault and Vault Enterprise 1.5.1 and newer, under certain circumstances, may exclude revoked but unexpired certificates from the CRL. Fixed in 1.5.8, 1.6.4, and 1.7.1.

An Improper Certificate Validation on UniFi OS devices, with Identity Enterprise configured, could allow a malicious actor to execute a man-in-the-middle (MitM) attack during application update.

The mechanism which performs certificate validation was discovered to have a flaw that resulted in certificates signed by an internal certificate authority to not be properly validated. This issue only affects clients that are configured to utilize Tenable.sc as the vulnerability data source.

libraries/libldap/tls_o.c in OpenLDAP 2.2 and 2.4, and possibly other versions, when OpenSSL is used, does not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

OSS Http Request (Apache Cordova Plugin) 6 is affected by: Missing SSL certificate validation. The impact is: certificate spoofing. The component is: use this library when https communication. The attack vector is: certificate spoofing.

When using an OCSP responder Apache Tomcat Native 1.2.0 to 1.2.16 and 1.1.23 to 1.1.34 did not correctly handle invalid responses. This allowed for revoked client certificates to be incorrectly identified. It was therefore possible for users to authenticate with revoked certificates when using mutual TLS. Users not using OCSP checks are not affected by this vulnerability.

IBM BigFix Remote Control before Interim Fix pack 9.1.2-TIV-IBRC912-IF0001 improperly allows self-signed certificates, which might allow remote attackers to conduct spoofing attacks via unspecified vectors. IBM X-Force ID: 105200.

Oracle MySQL before 5.7.3, Oracle MySQL Connector/C (aka libmysqlclient) before 6.1.3, and MariaDB before 5.5.44 use the --ssl option to mean that SSL is optional, which allows man-in-the-middle attackers to spoof servers via a cleartext-downgrade attack, aka a "BACKRONYM" attack.

Restkit allows man-in-the-middle attackers to spoof TLS servers by leveraging use of the ssl.wrap_socket function in Python with the default CERT_NONE value for the cert_reqs argument.

rhnreg_ks in Red Hat Network Client Tools (aka rhn-client-tools) on Red Hat Gluster Storage 2.1 and Enterprise Linux (RHEL) 5, 6, and 7 does not properly validate hostnames in X.509 certificates from SSL servers, which allows remote attackers to prevent system registration via a man-in-the-middle attack.

vdsm and vdsclient does not validate certficate hostname from another vdsm which could facilitate a man-in-the-middle attack

Emissary-Ingress (formerly Ambassador API Gateway) through 1.13.9 allows attackers to bypass client certificate requirements (i.e., mTLS cert_required) on backend upstreams when more than one TLSContext is defined and at least one configuration exists that does not require client certificate authentication. The attacker must send an SNI specifying an unprotected backend and an HTTP Host header specifying a protected backend. (2.x versions are unaffected. 1.x versions are unaffected with certain configuration settings involving prune_unreachable_routes and a wildcard Host resource.)

jxbrowser in TI Code Composer Studio IDE 8.x through 10.x before 10.1.1 does not verify X.509 certificates for HTTPS.

A certificate validation issue was addressed. This issue is fixed in iOS 14.5 and iPadOS 14.5. An attacker in a privileged network position may be able to alter network traffic.

There is Missing SSL Certificate Validation in the Trend Micro Enterprise Mobile Security Android Application before 9.7.1193, aka VRTS-398.