OpenSSL vulnerabilities
We track 61 vulnerabilities in OpenSSL products. 61 are rated high or critical, and 1 has been exploited in real attacks. The most recent was published on September 29, 2026.
Latest OpenSSL vulnerabilities
- 7.5 High severity
OpenSSL: Access of Resource Using Incompatible Type
Issue summary: Applications performing certificate name checks (e.g., TLS clients checking server certificates) may attempt to read an invalid memory address resulting in abnormal termination of the application process. Impact summary: Abnormal termination of
- 9.1 Critical severity
OpenSSL: Out-of-bounds Read
Issue summary: Calling the OpenSSL API function SSL_select_next_proto with an empty supported client protocols buffer may cause a crash or memory contents to be sent to the peer. Impact summary: A buffer overread can have a range of potential consequences such
- 7.5 High severity
OpenSSL: Incorrect Provision of Specified Functionality
Issue summary: A bug has been identified in the processing of key and initialisation vector (IV) lengths. This can lead to potential truncation or overruns during the initialisation of some symmetric ciphers. Impact summary: A truncation in the IV can result i
- 7.8 High severity
OpenSSL: Expected Behavior Violation
Issue summary: The POLY1305 MAC (message authentication code) implementation contains a bug that might corrupt the internal state of applications on the Windows 64 platform when running on newer X86_64 processors supporting the AVX512-IFMA instructions. Impact
- 7.5 High severity
OpenSSL: Improper Certificate Validation
A security vulnerability has been identified in all supported versions of OpenSSL related to the verification of X.509 certificate chains that include policy constraints. Attackers may be able to exploit this vulnerability by creating a malicious certificate c
- 7.5 High severity
OpenSSL: NULL Pointer Dereference
A NULL pointer can be dereferenced when signatures are being verified on PKCS7 signed or signedAndEnveloped data. In case the hash algorithm used for the signature is known to the OpenSSL library but the implementation of the hash algorithm is not available th
- 7.4 High severity
OpenSSL: Access of Resource Using Incompatible Type
There is a type confusion vulnerability relating to X.400 address processing inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING but the public structure definition for GENERAL_NAME incorrectly specified the type of the x400Address field
- 7.5 High severity
OpenSSL: NULL Pointer Dereference
An invalid pointer dereference on read can be triggered when an application tries to check a malformed DSA public key by the EVP_PKEY_public_check() function. This will most likely lead to an application crash. This function can be called on public keys suppli
- 7.5 High severity
OpenSSL: NULL Pointer Dereference
An invalid pointer dereference on read can be triggered when an application tries to load malformed PKCS7 data with the d2i_PKCS7(), d2i_PKCS7_bio() or d2i_PKCS7_fp() functions. The result of the dereference is an application crash which could lead to a denial
- 7.5 High severity
OpenSSL: Use After Free
The public API function BIO_new_NDEF is a helper function used for streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL to support the SMIME, CMS and PKCS7 streaming capabilities, but may also be called directly by end user applications.
- 7.5 High severity
OpenSSL: Double Free
The function PEM_read_bio_ex() reads a PEM file from a BIO and parses and decodes the "name" (e.g. "CERTIFICATE"), any header data and the payload data. If the function succeeds then the "name_out", "header" and "data" arguments are populated with pointers to
- 7.5 High severity
OpenSSL: Improper Locking
If an X.509 certificate contains a malformed policy constraint and policy processing is enabled, then a write lock will be taken twice recursively. On some operating systems (most widely: Windows) this results in a denial of service when the affected process h
- 7.5 High severity
OpenSSL: Buffer Copy without Checking Size of Input
A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed a malicious certificate or for an applic
- 7.5 High severity
OpenSSL: Out-of-bounds Write
A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the app
- 7.5 High severity
OpenSSL: NULL Pointer Dereference
OpenSSL supports creating a custom cipher via the legacy EVP_CIPHER_meth_new() function and associated function calls. This function was deprecated in OpenSSL 3.0 and application authors are instead encouraged to use the new provider mechanism in order to impl
- 9.8 Critical severity
OpenSSL: Out-of-bounds Write
The OpenSSL 3.0.4 release introduced a serious bug in the RSA implementation for X86_64 CPUs supporting the AVX512IFMA instructions. This issue makes the RSA implementation with 2048 bit private keys incorrect on such machines and memory corruption will happen
- 7.3 High severity
OpenSSL: Improper Neutralization of Special Elements used in an OS Command
In addition to the c_rehash shell command injection identified in CVE-2022-1292, further circumstances where the c_rehash script does not properly sanitise shell metacharacters to prevent command injection were found by code review. When the CVE-2022-1292 was
- 7.5 High severity
OpenSSL: Incomplete Cleanup
The OPENSSL_LH_flush() function, which empties a hash table, contains a bug that breaks reuse of the memory occuppied by the removed hash table entries. This function is used when decoding certificates or keys. If a long lived process periodically decodes cert
- 7.3 High severity
OpenSSL: Improper Neutralization of Special Elements used in an OS Command
The c_rehash script does not properly sanitise shell metacharacters to prevent command injection. This script is distributed by some operating systems in a manner where it is automatically executed. On such operating systems, an attacker could execute arbitrar
- 7.5 High severity
OpenSSL: Loop with Unreachable Exit Condition
The BN_mod_sqrt() function, which computes a modular square root, contains a bug that can cause it to loop forever for non-prime moduli. Internally this function is used when parsing certificates that contain elliptic curve public keys in compressed form or ex
- 7.5 High severity
OpenSSL Information Disclosure Exploited
The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly handle Heartbeat Extension packets, which allows remote attackers to obtain sensitive information from process memory via crafted packets that trigger a buffer over-read, a