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.

It was found that CloudForms does not verify that the server hostname matches the domain name in the certificate when using a custom CA and communicating with Red Hat Virtualization (RHEV) and OpenShift. This would allow an attacker to spoof RHEV or OpenShift systems and potentially harvest sensitive information from CloudForms.

It was discovered that rpm-ostree and rpm-ostree-client before 2017.3 fail to properly check GPG signatures on packages when doing layering. Packages with unsigned or badly signed content could fail to be rejected as expected. This issue is partially mitigated on RHEL Atomic Host, where certificate pinning is used by default.

In RHEV-M VDC 2.2.0, it was found that the SSL certificate was not verified when using the client-side Red Hat Enterprise Virtualization Manager interface (a Windows Presentation Foundation (WPF) XAML browser application) to connect to the Red Hat Enterprise Virtualization Manager. An attacker on the local network could use this flaw to conduct a man-in-the-middle attack, tricking the user into thinking they are viewing the Red Hat Enterprise Virtualization Manager when the content is actually attacker-controlled, or modifying actions a user requested Red Hat Enterprise Virtualization Manager to perform.

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.

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

Improper Certificate Validation vulnerability in Erlang OTP public_key (pubkey_cert and public_key modules) allows a DNS nameConstraints bypass via subject CommonName fallback in TLS hostname verification. Two flaws combine to allow a subordinate CA whose DNS nameConstraints are restricted (e.g. permitted;DNS:allowed.example.com) to issue a leaf certificate that an OTP TLS client accepts as a valid identity for an out-of-scope hostname (e.g. victim.example.com): First, pubkey_cert:validate_names/6 in lib/public_key/src/pubkey_cert.erl only checks SAN DNS entries against nameConstraints. Per RFC 5280, a permitted DNS subtree only restricts certificates that contain a DNS-typed name. A leaf with no subjectAltName therefore trivially satisfies any permitted;DNS:... constraint regardless of its subject commonName. Second, public_key:pkix_verify_hostname/3 in lib/public_key/src/public_key.erl falls back to the subject commonName when no subjectAltName is present, extracting id-at-commonName attributes as presented IDs and matching them against the reference hostname. The strict pkix_verify_hostname_match_fun(https) matcher does not suppress this fallback. The result is that path validation accepts a CN-only leaf under a DNS-constrained intermediate (no SAN means the nameConstraints are not triggered), and hostname verification then accepts it via the CN fallback. The bypass is reachable from stock ssl:connect with verify_peer, a trusted CA, SNI, and the canonical strict https hostname matcher. This issue affects OTP from OTP 19.3 before OTP 29.0.1, OTP 28.5.0.1, OTP 27.3.4.12 and OTP 26.2.5.21, corresponding to public_key from 1.4 before 1.21.1, 1.20.3.1, 1.17.1.3 and 1.15.1.7.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.

A flaw was found in gnutls. When validating certificates, an oversized Subject Alternative Name (SAN) could cause the validation process to incorrectly fall back to checking the Common Name (CN) field. This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.

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.

GnuTLS before 3.3.13 does not validate that the signature algorithms match when importing a certificate.

When libvirtd is configured by OSP director (tripleo-heat-templates) to use the TLS transport it defaults to the same certificate authority as all non-libvirtd services. As no additional authentication is configured this allows these services to connect to libvirtd (which is equivalent to root access). If a vulnerability exists in another service it could, combined with this flaw, be exploited to escalate privileges to gain control over compute nodes.

Botan is a C++ cryptography library. In 3.11.0, the function Certificate_Store::certificate_known had a misleading name; it would return true if any certificate in the store had a DN (and subject key identifier, if set) matching that of the argument. It did not check that the cert it found and the cert it was passed were actually the same certificate. In 3.11.0 an extension of path validation logic was made which assumed that certificate_known only returned true if the certificates were in fact identical. The impact is that if an end entity certificate is presented, and its DN (and subject key identifier, if set) match that of any trusted root, the end entity certificate is accepted immediately as if it itself were a trusted root. , This vulnerability is fixed in 3.11.1.

Forge (also called `node-forge`) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, `pki.verifyCertificateChain()` does not enforce RFC 5280 basicConstraints requirements when an intermediate certificate lacks both the `basicConstraints` and `keyUsage` extensions. This allows any leaf certificate (without these extensions) to act as a CA and sign other certificates, which node-forge will accept as valid. Version 1.4.0 patches the issue.

When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly applied, and only the last constraint will be considered.

Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof PTR records to impersonate ZooKeeper servers or clients with a valid certificate for the PTR name. It's important to note that attacker must present a certificate which is trusted by ZKTrustManager which makes the attack vector harder to exploit. Users are recommended to upgrade to version 3.8.6 or 3.9.5, which fixes this issue by introducing a new configuration option to disable reverse DNS lookup in client and quorum protocols.

dirmngr before 2.1.0 improperly handles certain system calls, which allows remote attackers to cause a denial of service (DOS) via a specially-crafted certificate.

A insecure configuration for certificate verification (http.verify_mode = OpenSSL::SSL::VERIFY_NONE) may lead to verification bypass in Red Hat CloudForms 5.x.

When PgBouncer is configured to use "cert" authentication, a man-in-the-middle attacker can inject arbitrary SQL queries when a connection is first established, despite the use of TLS certificate verification and encryption. This flaw affects PgBouncer versions prior to 1.16.1.

Vulnerability in Spring Spring Security. SubjectX500PrincipalExtractor does not correctly handle certain malformed X.509 certificate CN values, which can lead to reading the wrong value for the username. In a carefully crafted certificate, this can lead to an attacker impersonating another user. This issue affects Spring Security: from 7.0.0 through 7.0.4.

It was found in OpenShift, before version 4.8, that the generated certificate for the in-cluster Service CA, incorrectly included additional certificates. The Service CA is automatically mounted into all pods, allowing them to safely connect to trusted in-cluster services that present certificates signed by the trusted Service CA. The incorrect inclusion of additional CAs in this certificate would allow an attacker that compromises any of the additional CAs to masquerade as a trusted in-cluster service.

A flaw was found in all Openshift Enterprise versions using the openshift elasticsearch plugin. An attacker with knowledge of the given name used to authenticate and access Elasticsearch can later access it without the token, bypassing authentication. This attack also requires that the Elasticsearch be configured with an external route, and the data accessed is limited to the indices.

A flaw was found in keycloak affecting versions 11.0.3 and 12.0.0. An expired certificate would be accepted by the direct-grant authenticator because of missing time stamp validations. The highest threat from this vulnerability is to data confidentiality and integrity.

A flaw was found in JBCS httpd in version 2.4.37 SP3, where it uses a back-end worker SSL certificate with the keystore file's ID is 'unknown'. The validation of the certificate whether CN and hostname are matching stopped working and allow connecting to the back-end work. The highest threat from this vulnerability is to data integrity.

A flaw was found in Keycloak in versions before 10.0.0, where it does not perform the TLS hostname verification while sending emails using the SMTP server. This flaw allows an attacker to perform a man-in-the-middle (MITM) attack.

libldap in certain third-party OpenLDAP packages has a certificate-validation flaw when the third-party package is asserting RFC6125 support. It considers CN even when there is a non-matching subjectAltName (SAN). This is fixed in, for example, openldap-2.4.46-10.el8 in Red Hat Enterprise Linux.

ovirt-engine, as used in Red Hat MRG 3, allows man-in-the-middle attackers to spoof servers by leveraging failure to verify key attributes in vdsm X.509 certificates.

An Improper Certificate Validation attack was found in Openshift. A re-encrypt Route with destinationCACertificate explicitly set to the default serviceCA skips internal Service TLS certificate validation. This flaw allows an attacker to exploit an invalid certificate, resulting in a loss of confidentiality.

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).

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.

It was found that Kubernetes as used by Openshift Enterprise 3 did not correctly validate X.509 client intermediate certificate host name fields. An attacker could use this flaw to bypass authentication requirements by using a specially crafted X.509 certificate.

Shotwell version 0.22.0 (and possibly other versions) is vulnerable to a TLS/SSL certification validation flaw resulting in a potential for man in the middle attacks.

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.

IBM Security Verify Access 10.0.0.0 through 10.0.6.1 could allow a privileged user to install a configuration file that could allow remote access. IBM X-Force ID: 266155.