JLSEC-2026-258 Issue summary: The 'openssl dgst' command-line tool silently truncates input data to 16MB when using...

Issue summary: The 'openssl dgst' command-line tool silently truncates input data to 16MB when using one-shot signing algorithms and reports success instead of an error. Impact summary: A user signing or verifying files larger than 16MB with one-shot algorithms such as Ed25519, Ed448, or ML-DSA m...

JLSEC-2026-235 A security vulnerability has been identified in all supported versions

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 chain that triggers exponential use of...

JLSEC-2026-245 Issue summary: The POLY1305 MAC (message authentication code) implementation contains a bug that...

Issue summary: The POLY1305 MAC message authentication code implementation contains a bug that might corrupt the internal state of applications running on PowerPC CPU based platforms if the CPU provides vector instructions. Impact summary: If an attacker can influence whether the POLY1305 MAC...

JLSEC-2026-240 Issue summary: The AES-SIV cipher implementation contains a bug that causes it to ignore empty...

Issue summary: The AES-SIV cipher implementation contains a bug that causes it to ignore empty associated data entries which are unauthenticated as a consequence. Impact summary: Applications that use the AES-SIV algorithm and want to authenticate empty data entries as associated data can be misl...

JLSEC-2026-233 openssl-src vulnerable to Use-after-free following `BIO_new_NDEF`

The public API function BIOnewNDEF 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. The function receives a BIO from the...

JLSEC-2026-247 Null pointer dereference in PKCS12 parsing

Issue summary: Processing a maliciously formatted PKCS12 file may lead OpenSSL to crash leading to a potential Denial of Service attack Impact summary: Applications loading files in the PKCS12 format from untrusted sources might terminate abruptly. A file in PKCS12 format can contain certificates...

JLSEC-2026-216 There is an overflow bug in the `x64_64` Montgomery squaring procedure used in exponentiation with...

There is an overflow bug in the x6464 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are...

JLSEC-2026-265 Issue summary: Processing a malformed PKCS#12 file can trigger a NULL pointer dereference in the...

Issue summary: Processing a malformed PKCS12 file can trigger a NULL pointer dereference in the PKCS12itemdecryptd2iex function. Impact summary: A NULL pointer dereference can trigger a crash which leads to Denial of Service for an application processing PKCS12 files. The PKCS12itemdecryptd2iex...

JLSEC-2026-242 Issue summary: The POLY1305 MAC (message authentication code) implementation contains a bug that...

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 X8664 processors supporting the AVX512-IFMA instructions. Impact summary: If in an application that uses...

JLSEC-2026-217 OpenSSL has internal defaults for a directory tree where it can find a configuration file as well as...

OpenSSL has internal defaults for a directory tree where it can find a configuration file as well as certificates used for verification in TLS. This directory is most commonly referred to as OPENSSLDIR, and is configurable with the --prefix / --openssldir configuration options. For OpenSSL versio...

JLSEC-2026-219 Null pointer deference in openssl-src

Server or client applications that call the SSLcheckchain function during or after a TLS 1.3 handshake may crash due to a NULL pointer dereference as a result of incorrect handling of the "signaturealgorithmscert" TLS extension. The crash occurs if an invalid or unrecognised signature algorithm i...

JLSEC-2026-223 openssl-src NULL pointer Dereference in `signature_algorithms` processing

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 NU...

JLSEC-2026-236 Applications that use a non-default option when verifying certificates may be vulnerable to an...

Applications that use a non-default option when verifying certificates may be vulnerable to an attack from a malicious CA to circumvent certain checks. Invalid certificate policies in leaf certificates are silently ignored by OpenSSL and other certificate policy checks are skipped for that...

JLSEC-2026-218 In situations where an attacker receives automated notification of the success or failure of a...

In situations where an attacker receives automated notification of the success or failure of a decryption attempt an attacker, after sending a very large number of messages to be decrypted, can recover a CMS/PKCS7 transported encryption key or decrypt any RSA encrypted message that was encrypted...

JLSEC-2026-229 In addition to the `c_rehash` shell command injection identified in CVE-2022-1292, further...

In addition to the crehash shell command injection identified in CVE-2022-1292, further circumstances where the crehash script does not properly sanitise shell metacharacters to prevent command injection were found by code review. When the CVE-2022-1292 was fixed it was not discovered that there...

JLSEC-2026-230 AES OCB fails to encrypt some bytes

AES OCB mode for 32-bit x86 platforms using the AES-NI assembly optimised implementation will not encrypt the entirety of the data under some circumstances. This could reveal sixteen bytes of data that was preexisting in the memory that wasn't written. In the special case of "in place" encryption...

JLSEC-2026-277 Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can...

Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer. Impact summary: The uninitialized buffer might contain sensitive data from the previous execution of the application process whi...

JLSEC-2026-232 openssl-src contains Double free after calling `PEM_read_bio_ex`

The function PEMreadbioex 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 "nameout", "header" and "data" arguments are populated with pointers to buffers containing the relevant decoded data...

JLSEC-2026-259 Issue summary: Use of -addreject option with the openssl x509 application adds a trusted use instead...

Issue summary: Use of -addreject option with the openssl x509 application adds a trusted use instead of a rejected use for a certificate. Impact summary: If a user intends to make a trusted certificate rejected for a particular use it will be instead marked as trusted for that use. A copy & paste...

JLSEC-2026-252 Issue summary: Calling the OpenSSL API function `SSL_select_next_proto` with an empty supported...

Issue summary: Calling the OpenSSL API function SSLselectnextproto 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 as unexpected application beahviour or ...