CVE-2026-55964

CVE-2026-55964 describes a change in certificate path validation affecting OpenSSL-compatibility path building (X509_verify_cert / X509_STORE). Previously, chain-supplied temporary CAs (WOLFSSL_TEMP_CA) could be accepted as signing CAs even if the intermediate CA had CA:TRUE but lacked keyCertSig...

EUVD-2026-39544

Chain intermediate CA:TRUE without keyCertSign accepted as a signing CA. Intermediate CA certificates are required to have the keyCertSign key usage when a Key Usage extension is present, but chain-supplied temporary CAs WOLFSSLTEMPCA added while building a certificate path were previously exempt...

python-pyjwt: PyJWT: Authentication bypass due to forged JSON Web Tokens

A flaw was found in PyJWT, a Python library for JSON Web Token JWT implementation. When decoding JWTs, the library fails to validate the use of JSON Web Keys JWK in the HMAC algorithm while also supporting asymmetric algorithms. This allows a remote attacker to use the issuer's public key as the...

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-2026-45389

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-2026-45388

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-2026-8367

aria2c accepts a server certificate with incorrect Extended Key Usage EKU. If the attackers compromise a certificate with the associated private key issued for a different purpose, they may be able to reuse it for TLS server authentication...

CVE-2026-42789

Improper Following of a Certificate's Chain of Trust vulnerability in Erlang OTP publickey pubkeycert module allows a non-CA certificate to be accepted as an intermediate issuer, enabling certificate chain forgery. In lib/publickey/src/pubkeycert.erl, pubkeycert:validateextensions/7 contains two...

CVE-2026-42789

Improper Following of a Certificate's Chain of Trust vulnerability in Erlang OTP publickey pubkeycert module allows a non-CA certificate to be accepted as an intermediate issuer, enabling certificate chain forgery. In lib/publickey/src/pubkeycert.erl, pubkeycert:validateextensions/7 contains two...

CVE-2026-42789

The CVE-2026-42789 entry documents a vulnerability in Erlang OTP public_key (pubkey_cert module): a certificate with basicConstraints cA:false and no keyUsage can be misused as an intermediate issuer during pkix_path_validation, enabling chain forgery. Two flaws in pubkey_cert:validate_extensions...

EEF-CVE-2026-42789 Non-CA certificate accepted as intermediate issuer in public_key path validation

Summary Improper Following of a Certificate's Chain of Trust vulnerability in Erlang OTP publickey pubkeycert module allows a non-CA certificate to be accepted as an intermediate issuer, enabling certificate chain forgery. In lib/publickey/src/pubkeycert.erl, pubkeycert:validateextensions/7...

PT-2026-43712

Name of the Vulnerable Software and Affected Versions Erlang OTP versions 17.0 through 26.2.5.20 Erlang OTP versions 27.x prior to 27.3.4.12 Erlang OTP versions 28.x prior to 28.5.0.1 Erlang OTP versions 29.x prior to 29.0.1 public key versions 0.22 through 1.15.1.6 public key versions 1.17.x pri...

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-2026-06 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...

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...

PT-2026-42203

Name of the Vulnerable Software and Affected Versions OCaml-TLS versions prior to 2.1.0 Description The server implementation fails to properly validate the KeyUsage and ExtendedKeyUsage extensions of certificates provided by clients during mutual TLS mTLS authentication. This allows an attacker ...