OpenSSL could allow a remote attacker to bypass security restrictions, caused by a a missing check in the validation logic of X.509 certificate chains by the X509VFLAGX509STRICT flag. By using any valid certificate or certificate chain to sign a specially crafted certificate, an attacker could bypass the check that non-CA certificates must not be able to issue other certificates and override the default purpose.

An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signaturealgorithms extension (where it was present in the initial ClientHello), but includes a signaturealgorithmscert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

A null pointer dereference flaw was found in openssl. A remote attacker, able to control the arguments of the GENERALNAMEcmp function, could cause the application, compiled with openssl to crash resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Calls to EVPCipherUpdate, EVPEncryptUpdate and EVPDecryptUpdate may overflow the output length argument in some cases where the input length is close to the maximum permissable length for an integer on the platform. In such cases the return value from the function call will be 1 (indicating success), but the output length value will be negative. This could cause applications to behave incorrectly or crash. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x).

Last updated 24 July 2024

A flaw was found in the way curl handled telnet protocol option for sending environment variables, which could lead to sending of uninitialized data from a stack-based buffer to the server. This issue leads to potentially revealing sensitive internal information to the server using a clear-text network protocol.

Last updated 25 August 2025