Improper Certificate Validation

epa4all-client is the Java Client for epa4all / ePA 3.0 in the Telematik Infrastruktur. Prior to 1.2.2, an attacker on the network path between the ePA service and the Konnektor can present any TLS certificate (self-signed, expired, wrong CN) and intercept all SOAP traffic. This includes patient identifiers (KVNR), SMC-B card operations (authentication, signing), document content, and credential exchanges. This vulnerability is fixed in 1.2.2.Show less

epa4all-client is the Java Client for epa4all / ePA 3.0 in the Telematik Infrastruktur. Prior to 1.2.1, in SignedPublicKeysTrustValidatorImpl.isTrusted(), the ECDSA signature verification at line 45 discards the boolean return value of Signature.verify(). The method performs certificate chain validation, OCSP check, and signature algorithm setup, but never checks whether the signature actually matches. For any structurally valid signature, it returns true. This vulnerability is fixed in 1.2.1.Show less

The OpenTelemetry.Exporter.Instana exports telemetry to Instana backend. Prior to 1.1.0, the OpenTelemetry.Exporter.Instana NuGet package does not validate HTTPS/TLS certificates are valid when sending telemetry to a configured Instana back-end when a proxy is configured using the INSTANA_ENDPOINT_PROXY environment variable. If a network attacker can Man-in-the-Middle (MitM) the proxy connection, all OpenTelemetry telemetry data and the Instana API key are exposed to the attacker. This vulnerability is fixed in 1.1.0.Show less

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.Show less

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.Show less

FastNetMon Community Edition through 1.2.9 does not verify TLS certificates on outbound HTTPS connections. The execute_web_request_secure() function in src/fast_library.cpp creates a boost::asio::ssl::context with tls_client mode and calls set_default_verify_paths() to load CA certificates, but never calls set_verify_mode(boost::asio::ssl::verify_peer). Without this call, OpenSSL performs the TLS handshake without validating the server's certificate chain, making all HTTPS connections vulnerable to man-in-the-middle attacks. This function is used for telemetry reporting to community-stats.fastnetmon.com, which sends system information including CPU model, kernel version, traffic statistics, and software configuration. An attacker can intercept and modify this data or redirect it to a malicious server.Show less

For untrusted certificates that contain the "Authority Information Access - caIssuers URI" extension, Szafir SDK will automatically download the parent CA certificate from the specified URL and will import it to its trust store as a "nonqualified" certificate. In such a case, Szafir SDK returns a success status code of 0 ("Positively verified") upon successful cryptographic verification and a certificate status of "nonqualified". For other types of untrusted certificates, Szafir SDK returns a success status code of 0 ("Positively verified") upon successful cryptographic verification and a certificate status of "nondetermined". This may lead integrating applications to incorrectly treat the digital signature as valid despite an untrusted certificate chain. This flaw enables authentication bypass and user impersonation: (1) in use-cases other than qualified certificate authentication, or (2) if the qualified certificate authentication use-case is not correctly implemented by the integrating application. This issue was fixed in version 1.8.463.2.Show less

Sunshine is a self-hosted game stream host for Moonlight. In versions prior to 2026.516.143833, the client-certificate authentication can be bypassed because of how OpenSSL verification results are handled. In src/crypto.cpp, the custom verify callback treats X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY, X509_V_ERR_CERT_NOT_YET_VALID, and X509_V_ERR_CERT_HAS_EXPIRED as success. This can allow an untrusted certificate to pass authentication and access protected HTTPS endpoints. This issue has been fixed in version 2026.516.143833.Show less

Dell PowerFlex Manager, version(s) <=4.6.2, contain(s) an Improper Certificate Validation vulnerability. An unauthenticated attacker with adjacent network access could potentially exploit this vulnerability, leading to Information tampering.Show less

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.Show less

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.Show less

Open ISES Tickets before 3.44.2 disables TLS certificate verification in rm/incs/mobile_login.inc.php by setting CURLOPT_SSL_VERIFYPEER to false (and not setting CURLOPT_SSL_VERIFYHOST) when issuing outbound HTTPS requests issued during the mobile (RouteMate) login flow. An attacker positioned on the network path between the server and the remote endpoint can present a forged certificate to intercept, monitor, or modify the request and response, including any API keys or session-bearing data in transit.Show less

Open ISES Tickets before 3.44.2 disables TLS certificate verification in incs/login.inc.php by setting CURLOPT_SSL_VERIFYPEER to false (and not setting CURLOPT_SSL_VERIFYHOST) when issuing outbound HTTPS requests issued during the login/authentication flow. An attacker positioned on the network path between the server and the remote endpoint can present a forged certificate to intercept, monitor, or modify the request and response, including any API keys or session-bearing data in transit.Show less

Open ISES Tickets before 3.44.2 disables TLS certificate verification in incs/functions.inc.php by setting CURLOPT_SSL_VERIFYPEER to false (and not setting CURLOPT_SSL_VERIFYHOST) when issuing outbound HTTPS requests for general-purpose outbound HTTPS requests issued by the shared helper functions. An attacker positioned on the network path between the server and the remote endpoint can present a forged certificate to intercept, monitor, or modify the request and response, including any API keys or session-bearing data in transit.Show less

Open ISES Tickets before 3.44.2 disables TLS certificate verification in ajax/reports.php by setting CURLOPT_SSL_VERIFYPEER to false (and not setting CURLOPT_SSL_VERIFYHOST) when issuing outbound HTTPS requests for Google Maps Directions API lookups during incident report generation. An attacker positioned on the network path between the server and the remote endpoint can present a forged certificate to intercept, monitor, or modify the request and response, including any API keys or session-bearing data in transit.Show less

Dell Live Optics Windows and Personal Edition collectors contain an improper certificate validation vulnerability. A remote unauthenticated attacker could potentially exploit this vulnerability leading to loss of confidentiality and integrity.Show less

Gitsign is a keyless Sigstore to signing tool for Git commits with your a GitHub / OIDC identity. Prior to 0.16.0, gitsign verify and gitsign verify-tag re-encode commit/tag objects through go-git's EncodeWithoutSignature before checking the signature, instead of verifying against the raw git object bytes. For malformed objects with duplicate tree headers, git-core and go-git parse different trees: git-core uses the first, go-git uses the second. A signature crafted over the go-git-normalized form (second tree) passes gitsign verify while git-core resolves the commit to a completely different tree. This breaks the invariant that a verified signature, the commit semantics git-core presents to users, and the object hash logged in Rekor all refer to the same content. This vulnerability is fixed in 0.16.0.Show less

Elixir WebRTC is an Elixir implementation of the W3C WebRTC API. Prior to 0.15.1 and 0.16.1, missing DTLS peer certificate fingerprint validation in the DTLS client (active) role removes one side of WebRTC's mutual authentication. The bug is not independently exploitable for media interception in standard deployments, but enables a full man-in-the-middle attack when chained with insecure signalling or a peer with similar validation gaps. This vulnerability is fixed in 0.15.1 and 0.16.1.Show less