The Socket Appender in Apache Log4j Core versions 2.0-beta9 through 2.25.2 does not perform TLS hostname verification of the peer certificate, even when the verifyHostName https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName configuration attribute or the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName system property is set to true. This issue may allow a man-in-the-middle attacker to intercept or redirect log traffic under the following conditions: * The attacker is able to intercept or redirect network traffic between the client and the log receiver. * The attacker can present a server certificate issued by a certification authority trusted by the Socket Appender’s configured trust store (or by the default Java trust store if no custom trust store is configured). Users are advised to upgrade to Apache Log4j Core version 2.25.3, which addresses this issue. As an alternative mitigation, the Socket Appender may be configured to use a private or restricted trust root to limit the set of trusted certificates.

Apache Libcloud before 0.11.1 uses an incorrect regular expression during verification of whether 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 a crafted certificate.

Apache Pulsar Brokers and Proxies create an internal Pulsar Admin Client that does not verify peer TLS certificates, even when tlsAllowInsecureConnection is disabled via configuration. The Pulsar Admin Client's intra-cluster and geo-replication HTTPS connections are vulnerable to man in the middle attacks, which could leak authentication data, configuration data, and any other data sent by these clients. An attacker can only take advantage of this vulnerability by taking control of a machine 'between' the client and the server. The attacker must then actively manipulate traffic to perform the attack. This issue affects Apache Pulsar Broker and Proxy versions 2.7.0 to 2.7.4; 2.8.0 to 2.8.3; 2.9.0 to 2.9.2; 2.10.0; 2.6.4 and earlier.

Delayed TLS hostname verification in the Pulsar Java Client and the Pulsar Proxy make each client vulnerable to a man in the middle attack. Connections from the Pulsar Java Client to the Pulsar Broker/Proxy and connections from the Pulsar Proxy to the Pulsar Broker are vulnerable. Authentication data is sent before verifying the server’s TLS certificate matches the hostname, which means authentication data could be exposed to an attacker. An attacker can only take advantage of this vulnerability by taking control of a machine 'between' the client and the server. The attacker must then actively manipulate traffic to perform the attack by providing the client with a cryptographically valid certificate for an unrelated host. Because the client sends authentication data before performing hostname verification, an attacker could gain access to the client’s authentication data. The client eventually closes the connection when it verifies the hostname and identifies the targeted hostname does not match a hostname on the certificate. Because the client eventually closes the connection, the value of the intercepted authentication data depends on the authentication method used by the client. Token based authentication and username/password authentication methods are vulnerable because the authentication data can be used to impersonate the client in a separate session. This issue affects Apache Pulsar Java Client versions 2.7.0 to 2.7.4; 2.8.0 to 2.8.3; 2.9.0 to 2.9.2; 2.10.0; 2.6.4 and earlier.

The Apache Bookkeeper Java Client (before 4.14.6 and also 4.15.0) does not close the connection to the bookkeeper server when TLS hostname verification fails. This leaves the bookkeeper client vulnerable to a man in the middle attack. The problem affects BookKeeper client prior to versions 4.14.6 and 4.15.1.

A bug in PSL validation logic in Apache HttpClient 5.4.x disables domain checks, affecting cookie management and host name verification. Discovered by the Apache HttpClient team. Fixed in the 5.4.3 release

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

Apache Airflow's EmailOperator and the underlying `airflow.utils.email` helpers established SMTP STARTTLS connections without verifying the remote certificate when the deployment used `[email] smtp_starttls=True` without `[email] smtp_ssl`. An attacker positioned between the worker and the configured SMTP server (network MITM — typical hostile-network attack-surface for environments where the SMTP relay sits outside the worker's trust boundary) could present a self-signed certificate, have the worker complete the STARTTLS handshake silently, and capture the SMTP AUTH credentials and message contents the worker forwarded. This CVE covers the **core apache-airflow side** of the same root cause already covered for the SMTP provider by `CVE-2026-41016` (published 2026-04-27, covering `apache-airflow-providers-smtp`). Users who already applied the SMTP-provider fix from CVE-2026-41016 should additionally upgrade `apache-airflow` to 3.2.2 or later to cover the core-side path through `airflow.utils.email`. Affects deployments configured with `smtp_starttls=True` and `smtp_ssl=False` where the SMTP relay is reachable across a less-trusted network segment than the worker. Users are advised to upgrade to `apache-airflow` 3.2.2 or later.

Improper Certificate Validation vulnerability in Apache Airflow FTP Provider. The FTP hook lacks complete certificate validation in FTP_TLS connections, which can potentially be leveraged. Implementing proper certificate validation by passing context=ssl.create_default_context() during FTP_TLS instantiation is used as mitigation to validate the certificates properly. This issue affects Apache Airflow FTP Provider: before 3.7.0. Users are recommended to upgrade to version 3.7.0, which fixes the issue.

Improper Validation of Certificate with Host Mismatch vulnerability in Apache Thrift. This issue affects Apache Thrift: before 0.23.0. Users are recommended to upgrade to version 0.23.0, which fixes the issue.

When ssl was enabled for Mongo Hook, default settings included "allow_insecure" which caused that certificates were not validated. This was unexpected and undocumented. Users are recommended to upgrade to version 4.0.0, which fixes this issue.

Improper Validation of Certificate with Host Mismatch vulnerability in Apache Thrift. This issue affects Apache Thrift: before 0.23.0. Users are recommended to upgrade to version 0.23.0, which fixes the issue.

The "Apache NetBeans" autoupdate system does not validate SSL certificates and hostnames for https based downloads. This allows an attacker to intercept downloads of autoupdates and modify the download, potentially injecting malicious code. “Apache NetBeans" versions up to and including 11.2 are affected by this vulnerability.

Improper Certificate Validation via Global SSL Context Downgrade in Apache Storm Prometheus Reporter Versions Affected: from 2.6.3 to 2.8.6 Description:  In production deployments where an administrator enables storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation (by default it is disabled) intending to affect only the Prometheus reporter, the undocumented global side effect creates an attack surface across every TLS-protected communication channel in the Storm daemon. The PrometheusPreparableReporter class implements an INSECURE_TRUST_MANAGER that accepts all SSL certificates without validation, with empty checkClientTrusted and checkServerTrusted methods. Most critically, when the storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation configuration option is enabled (default = disabled) for HTTPS Prometheus PushGateway connections, the INSECURE_CONNECTION_FACTORY calls SSLContext.setDefault(sslContext), which globally replaces the JVM's default SSL context rather than applying the insecure context only to the Prometheus connection. This payload flows through storm.yaml configuration → PrometheusPreparableReporter.prepare() → INSECURE_CONNECTION_FACTORY → SSLContext.setDefault(), resulting in a JVM-wide TLS security downgrade. All subsequent HTTPS connections in the process - including ZooKeeper, Thrift, Netty, and UI connections - silently trust all certificates, including self-signed, expired, and attacker-generated ones, enabling man-in-the-middle interception of cluster state, topology submissions, tuple data, and administrative credentials. Mitigation: 2.x users should upgrade to 2.8.7 if the Prometheus Metrics Reporter is used. Prometheus Metrics Reporter Users who cannot upgrade immediately should remove the storm.daemon.metrics.reporter.plugin.prometheus.skip_tls_validation: true setting from their storm.yaml configuration and instead configure a proper truststore containing the PushGateway's certificate.

The fix for CVE-2025-68161 https://logging.apache.org/security.html#CVE-2025-68161 was incomplete: it addressed hostname verification only when enabled via the log4j2.sslVerifyHostName https://logging.apache.org/log4j/2.x/manual/systemproperties.html#log4j2.sslVerifyHostName system property, but not when configured through the verifyHostName https://logging.apache.org/log4j/2.x/manual/appenders/network.html#SslConfiguration-attr-verifyHostName attribute of the <Ssl> element. Although the verifyHostName configuration attribute was introduced in Log4j Core 2.12.0, it was silently ignored in all versions through 2.25.3, leaving TLS connections vulnerable to interception regardless of the configured value. A network-based attacker may be able to perform a man-in-the-middle attack when all of the following conditions are met: * An SMTP, Socket, or Syslog appender is in use. * TLS is configured via a nested <Ssl> element. * The attacker can present a certificate issued by a CA trusted by the appender's configured trust store, or by the default Java trust store if none is configured. This issue does not affect users of the HTTP appender, which uses a separate verifyHostname https://logging.apache.org/log4j/2.x/manual/appenders/network.html#HttpAppender-attr-verifyHostName attribute that was not subject to this bug and verifies host names by default. Users are advised to upgrade to Apache Log4j Core 2.25.4, which corrects this issue.

Improper Certificate Validation vulnerability in Apache Airflow Provider for Databricks. Provider code did not validate certificates for connections to Databricks back-end which could result in a man-of-a-middle attack that traffic is intercepted and manipulated or credentials exfiltrated w/o notice. This issue affects Apache Airflow Provider for Databricks: from 1.10.0 before 1.12.0. Users are recommended to upgrade to version 1.12.0, which fixes the issue.

Because the HttpUtils class did not verify certificates, an attacker that could perform a Man-in-the-Middle (MITM) attack on outgoing https connections could impersonate the server. This issue affects Apache DolphinScheduler: before 3.2.0. Users are recommended to upgrade to version 3.2.1, which fixes the issue.

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.

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.

The host name verification when using TLS with the WebSocket client was missing. It is now enabled by default. Versions Affected: Apache Tomcat 9.0.0.M1 to 9.0.9, 8.5.0 to 8.5.31, 8.0.0.RC1 to 8.0.52, and 7.0.35 to 7.0.88.

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.

The LDAP auth backend (airflow.contrib.auth.backends.ldap_auth) prior to Apache Airflow 1.10.1 was misconfigured and contained improper checking of exceptions which disabled server certificate checking.

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.

Apache Thrift Java client library versions 0.5.0 through 0.11.0 can bypass SASL negotiation isComplete validation in the org.apache.thrift.transport.TSaslTransport class. An assert used to determine if the SASL handshake had successfully completed could be disabled in production settings making the validation incomplete.

Improper Input Validation vulnerability. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.14, from 10.1.0-M1 through 10.1.49, from 9.0.0-M1 through 9.0.112. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 through 8.5.100. Older EOL versions are not affected. Tomcat did not validate that the host name provided via the SNI extension was the same as the host name provided in the HTTP host header field. If Tomcat was configured with more than one virtual host and the TLS configuration for one of those hosts did not require client certificate authentication but another one did, it was possible for a client to bypass the client certificate authentication by sending different host names in the SNI extension and the HTTP host header field. The vulnerability only applies if client certificate authentication is only enforced at the Connector. It does not apply if client certificate authentication is enforced at the web application. Users are recommended to upgrade to version 11.0.15 or later, 10.1.50 or later or 9.0.113 or later, which fix the issue.

Apache Airflow SMTP Provider before 1.3.0, Apache Airflow IMAP Provider before 3.3.0, and Apache Airflow before 2.7.0 are affected by the Validation of OpenSSL Certificate vulnerability. The default SSL context with SSL library did not check a server's X.509 certificate.  Instead, the code accepted any certificate, which could result in the disclosure of mail server credentials or mail contents when the client connects to an attacker in a MITM position. Users are strongly advised to upgrade to Apache Airflow version 2.7.0 or newer, Apache Airflow IMAP Provider version 3.3.0 or newer, and Apache Airflow SMTP Provider version 1.3.0 or newer to mitigate the risk associated with this vulnerability

DroneScout ds230 Remote ID receiver from BlueMark Innovations is affected by an Improper Authentication vulnerability during the firmware update procedure. Specifically, the firmware update procedure ignores and does not check the validity of the TLS certificate of the HTTPS endpoint from which the firmware update package (.tar.bz2 file) is downloaded. An attacker with the ability to put himself in a Man-in-the-Middle situation (e.g., DNS poisoning, ARP poisoning, control of a node on the route to the endpoint, etc.) can trick the DroneScout ds230 to install a crafted malicious firmware update containing arbitrary files (e.g., executable and configuration) and gain administrative (root) privileges on the underlying Linux operating system. This issue affects DroneScout ds230 firmware from version 20211210-1627 through 20230329-1042.

The (1) update and (2) package-installation features in MODX Revolution 2.5.4-pl and earlier do not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and trigger the execution of arbitrary code via a crafted certificate.

Hammer CLI, a CLI utility for Foreman, before version 0.10.0, did not explicitly set the verify_ssl flag for apipie-bindings that disable it by default. As a result the server certificates are not checked and connections are prone to man-in-the-middle attacks.

The Motorola MH702x devices, prior to version 2.0.0.301, do not properly verify the server certificate during communication with the support server which could lead to the communication channel being accessible by an attacker.

DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without the corresponding certificate). The client side is affected because man-in-the-middle attackers can impersonate TLS 1.3 servers.

packages/wekan-ldap/server/ldap.js in Wekan before 4.87 can process connections even though they are not authorized by the Certification Authority trust store,

libvirt version 2.3.0 and later is vulnerable to a bad default configuration of "verify-peer=no" passed to QEMU by libvirt resulting in a failure to validate SSL/TLS certificates by default.

FreshService macOS Agent < 4.4.0 and FreshServce Linux Agent < 3.4.0 are vulnerable to TLS Man-in-The-Middle via the FreshAgent client and scheduled update service.

Wazuh provisioning scripts and Dockerfiles contain an insecure transport vulnerability where curl is invoked with the -k/--insecure flag, disabling SSL/TLS certificate validation. Attackers with network access can perform man-in-the-middle attacks to intercept and modify downloaded dependencies or code during the build process, leading to remote code execution and supply chain compromise.

Improper validation of the cloud certificate chain in Mobile Connect allows man-in-the-middle attack to impersonate the legitimate Command Centre Server. This issue affects: Gallagher Command Centre Mobile Connect for Android 15 versions prior to 15.04.040; version 14 and prior versions.

A flaw was found in all versions of kubeclient up to (but not including) v4.9.3, the Ruby client for Kubernetes REST API, in the way it parsed kubeconfig files. When the kubeconfig file does not configure custom CA to verify certs, kubeclient ends up accepting any certificate (it wrongly returns VERIFY_NONE). Ruby applications that leverage kubeclient to parse kubeconfig files are susceptible to Man-in-the-middle attacks (MITM).

Akerun - Smart Lock Robot App for iOS before 1.2.4 does not verify SSL certificates.

Busybox contains a Missing SSL certificate validation vulnerability in The "busybox wget" applet that can result in arbitrary code execution. This attack appear to be exploitable via Simply download any file over HTTPS using "busybox wget https://compromised-domain.com/important-file".

Dell EMC Unisphere for PowerMax versions prior to 9.1.0.17, Dell EMC Unisphere for PowerMax Virtual Appliance versions prior to 9.1.0.17, 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.

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.37.2, when a cpp-httplib client is configured with a proxy and set_follow_location(true), any HTTPS redirect it follows will have TLS certificate and hostname verification silently disabled on the new connection. The client will accept any certificate presented by the redirect target — expired, self-signed, or forged — without raising an error or notifying the application. A network attacker in a position to return a redirect response can fully intercept the follow-up HTTPS connection, including any credentials or session tokens in flight. This vulnerability is fixed in 0.37.2.

Vasion Print (formerly PrinterLogic) Virtual Appliance Host versions prior to 22.0.1049 and Application versions prior to 20.0.2786 (VA and SaaS deployments) contain insecure defaults and code patterns that disable TLS/SSL certificate verification for communications to printers and internal microservices. In multiple places, the application sets libcurl/PHP transport options such that CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER are effectively disabled, and environment variables (for example API_*_VERIFYSSL=false) are used to turn off verification for gateway and microservice endpoints. As a result, the client accepts TLS connections without validating server certificates (and, in some cases, uses clear-text HTTP), permitting on-path attackers to perform man-in-the-middle (MitM) attacks. An attacker able to intercept network traffic between the product and printers or microservices can eavesdrop on and modify sensitive data (including print jobs, configuration, and authentication tokens), inject malicious payloads, or disrupt service. This vulnerability has been identified by the vendor as: V-2024-024 — Insecure Communication to Printers & Microservices.

Strimzi provides a way to run an Apache Kafka cluster on Kubernetes or OpenShift in various deployment configurations. In versions 0.49.0 through 0.50.0, when using a custom Cluster or Clients CA with a multistage CA chain consisting of multiple CAs, Strimzi incorrectly configures the trusted certificates for mTLS authentication on the internal as well as user-configured listeners. All CAs from the CA chain will be trusted. And users with certificates signed by any of the CAs in the chain will be able to authenticate. This issue affects only users using a custom Cluster or Clients CA with a multistage CA chain consisting of multiple CAs. It does not affect users using the Strimzi-managed Cluster and Clients CAs. It also does not affect users using custom Cluster or Clients CA with only a single CA (i.e., no CA chain with multiple CAs). This issue has been fixed in version 0.50.1. To workaround this issue, instead of providing the full CA chain as the custom CA, users can provide only the single CA that should be used.

The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when built for Windows CE using the schannel TLS backend, makes it easier for remote attackers to conduct man-in-the-middle attacks via a crafted wildcard SAN in a server certificate, as demonstrated by "*.com."

In Apache::Session::Browseable before 1.3.6, validity of the X.509 certificate is not checked by default when connecting to remote LDAP backends, because the default configuration of the Net::LDAPS module for Perl is used. NOTE: this can, for example, be fixed in conjunction with the CVE-2020-16093 fix.

MiniTool Movie Maker 7.0 contains an insecure installation process that allows attackers to achieve remote code execution through a man in the middle attack.

Improper certificate validation in Ivanti ITSM on-prem and Neurons for ITSM Versions 2023.4 and earlier allows a remote attacker in a MITM position to craft a token that would allow access to ITSM as any user.

A flaw was found in the openstack-tripleo-common component of the Red Hat OpenStack Platform (RHOSP) director. This vulnerability allows an attacker to deploy potentially compromised container images via disabling TLS certificate verification for registry mirrors, which could enable a man-in-the-middle (MITM) attack.

An improper certificate validation vulnerability was reported in LADM that could allow a network attacker with the ability to redirect an update request to a remote server and execute code with elevated privileges.

qBittorrent before 5.0.1 proceeds with use of https URLs even after certificate validation errors.