CVE-2026-86881

CVE-2026-86881 is a certificate validation flaw in Apple platforms where an attacker with a compromised intermediate certificate authority may issue certificates with arbitrary extended key usages , potentially enabling unauthorized access to sensitive data or man-in-the-middle attacks. The issue...

CVE-2026-86881

A certificate validation issue was addressed with improved certificate validation. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An attacker with a compromised intermediate...

CVE-2026-67294

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

UBUNTU-CVE-2026-67294

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

EUVD-2026-51842

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

CVE-2026-67294

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

CVE-2026-67294

FreeRDP prior to 3.29.0 is affected by an EKU bypass in TLS server verification. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) validation fails, the code may fall back to client-purpose and any-purpose checks, allowing a certificate valid only for clientAuth to be treated ...

CVE-2026-67294 FreeRDP before 3.29.0 TLS Certificate EKU Bypass

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

CVE-2026-67294 FreeRDP before 3.29.0 TLS Certificate EKU Bypass

FreeRDP before 3.29.0 improperly validates the Extended Key Usage EKU purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify, when server-purpose X509PURPOSESSLSERVER verification fails, the code falls back to client-purpose and any-purpose verification, ...

PYSEC-2026-3051 rfc3161-client Has Improper Certificate Validation

Summary An Authorization Bypass vulnerability in rfc3161-client's signature verification allows any attacker to impersonate a trusted TimeStamping Authority TSA. By exploiting a logic flaw in how the library extracts the leaf certificate from an unordered PKCS7 bag of certificates, an attacker ca...

EUVD-2026-36764

In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with certificates that are not meant for server authentication because of KeyUsage and ExtendedKeyUsage...

EUVD-2026-36765

In OCaml-TLS before 2.1.0, the server implementation does insufficient checks of the certificate provided by the client when doing client authentication, which allows impersonation with certificates that are not meant for client authentication because of KeyUsage and ExtendedKeyUsage...

CVE-2026-45388

In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with certificates that are not meant for server authentication because of KeyUsage and ExtendedKeyUsage...

CVE-2026-45389

In OCaml-TLS before 2.1.0, the server implementation does insufficient checks of the certificate provided by the client when doing client authentication, which allows impersonation with certificates that are not meant for client authentication because of KeyUsage and ExtendedKeyUsage...

CVE-2026-45389

In OCaml-TLS before 2.1.0, the server implementation does insufficient checks of the certificate provided by the client when doing client authentication, which allows impersonation with certificates that are not meant for client authentication because of KeyUsage and ExtendedKeyUsage...

CVE-2026-45388

In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with certificates that are not meant for server authentication because of KeyUsage and ExtendedKeyUsage...

CVE-2026-45389

In OCaml-TLS before 2.1.0, the server implementation does insufficient checks of the certificate provided by the client when doing client authentication, which allows impersonation with certificates that are not meant for client authentication because of KeyUsage and ExtendedKeyUsage...

curl: curl GnuTLS backend accepts a clientAuth-only certificate for HTTPS server authentication

Summary: When curl/libcurl is built with the GnuTLS backend, the current HTTPS server-certificate validation path verifies the trust chain and hostname but does not enforce TLS server Extended Key Usage semantics. As a result, a leaf certificate that chains to a trusted CA, matches the requested...

OSEC-2026-07 TLS-server does insufficient client certificate checks (missing KeyUsage and ExtendedKeyUsage validation)

The TLS server implementation does not validate the KeyUsage and ExtendedKeyUsage extensions of client certificates when mutually authenticated TLS is requested. This can lead to impersonation with a certificate issued to a server. Scenario An operations engineer enables mTLS on the admin endpoin...

OSEC-2026-06 TLS-client (with TLS 1.3) does insufficient certificate checks (missing KeyUsage and ExtendedKeyUsage validation)

The ocaml-TLS 1.3 client does not validate the KeyUsage and ExtendedKeyUsage extensions of the server certificate. This can lead to impersonation with a certificate issued to a client. Scenario Every employee at a major bank carries a smart card. The card holds a clientAuth certificate issued by...