Nextcloud Server before 12.0.8 and 13.0.3 suffer from improper authentication on the OAuth2 token endpoint. Missing checks potentially allowed handing out new tokens in case the OAuth2 client was partly compromised.

Nextcloud Talk is a video and audio conferencing app for Nextcloud, a self-hosted productivity platform. Prior to versions 11.3.4, 12.2.2, and 13.0.0, when sharing a Deck card in conversation, the metaData can be manipulated so users can be tricked into opening arbitrary URLs. This issue is fixed in versions 11.3.4, 12.2.2, and 13.0.0. There are currently no known workarounds.

nextcloud news-android is an Android client for the Nextcloud news/feed reader app. In affected versions the Nextcloud News for Android app has a security issue by which a malicious application installed on the same device can send it an arbitrary Intent that gets reflected back, unintentionally giving read and write access to non-exported Content Providers in Nextcloud News for Android. Users should upgrade to version 0.9.9.63 or higher as soon as possible.

A missing verification of the TLS host in Nextcloud Mail 1.1.3 allowed a man in the middle attack.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. The Desktop client did not stop with an error but allowed by-passing the signature validation, if a manipulated server sends an empty initial signature. It is recommended that the Nextcloud Desktop client is upgraded to 3.14.2 or later.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.7.0, by trusting that the server will return a certificate that belongs to the keypair of the user, a malicious server could get the desktop client to encrypt files with a key known to the attacker. This issue is fixed in Nextcloud Desktop 3.7.0. No known workarounds are available.

Nextcloud also ships a CLI utility called nextcloudcmd which is sometimes used for automated scripting and headless servers. Versions of nextcloudcmd prior to 3.6.1 would incorrectly trust invalid TLS certificates, which may enable a Man-in-the-middle attack that exposes sensitive data or credentials to a network attacker. This affects the CLI only. It does not affect the standard GUI desktop Nextcloud clients, and it does not affect the Nextcloud server.

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.

Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account.

Nextcloud Desktop Client before 3.3.1 is vulnerable to improper certificate validation due to lack of SSL certificate verification when using the "Register with a Provider" flow.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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.

The Thycotic Password Manager Secret Server application through 2.3 for iOS 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.

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.

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

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.)

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.

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

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

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 kantan netprint App for iOS 2.0.2 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.

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 flaw was found in libnbd. The client did not always correctly verify the NBD server's certificate when using TLS to connect to an NBD server. This issue allows a man-in-the-middle attack on NBD traffic.

The kantan netprint App for Android 2.0.3 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 of NGINX Controller prior to 3.2.0, communication between NGINX Controller and NGINX Plus instances skip TLS verification by default.

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.

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.

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.

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.

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 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.

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.

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.