Vulnerabilidades do wolfSSL Wolfssl

CVE-2026-3548 Crítica · 9.8 CWE-787 19/03/2026

Buffer overflow in CRL number parsing in wolfSSL

Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when parsing CRL numbers: a heap-based buffer overflow could occur when improperly storing the CRL number as a hexadecimal string, and a stack-based overflow for sufficiently sized CRL numbers. With appropriately crafted CRLs, either of these out of bound writes could be triggered. Note this only affects builds that specifically enable CRL support, and the user would need to load a CRL from an untrusted source.

CVE-2026-2646 Alta · 8.1 CWE-787 19/03/2026

Heap buffer overflow in session parsing with wolfSSL_d2i_SSL_SESSION() function

A heap-buffer-overflow vulnerability exists in wolfSSL's wolfSSL_d2i_SSL_SESSION() function. When deserializing session data with SESSION_CERTS enabled, certificate and session id lengths are read from an untrusted input without bounds validation, allowing an attacker to overflow fixed-size buffers and corrupt heap memory. A maliciously crafted session would need to be loaded from an external source to trigger this vulnerability. Internal sessions were not vulnerable.

CVE-2026-2645 Alta · 7.5 CWE-358 19/03/2026

Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2

In wolfSSL 5.8.2 and earlier, a logic flaw existed in the TLS 1.2 server state machine implementation. The server could incorrectly accept the CertificateVerify message before the ClientKeyExchange message had been received. This issue affects wolfSSL before 5.8.4 (wolfSSL 5.8.2 and earlier is vulnerable, 5.8.4 is not vulnerable). In 5.8.4 wolfSSL would detect the issue later in the handshake. 5.9.0 was further hardened to catch the issue earlier in the handshake.

CVE-2026-1005 Média · 5.3 CWE-191 19/03/2026

Integer underflow leads to out-of-bounds access in sniffer AES-GCM/CCM/ARIA-GCM decrypt path

Integer underflow in wolfSSL packet sniffer <= 5.8.4 allows an attacker to cause a buffer overflow in the AEAD decryption path by injecting a TLS record shorter than the explicit IV plus authentication tag into traffic inspected by ssl_DecodePacket. The underflow wraps a 16-bit length to a large value that is passed to AEAD decryption routines, causing heap buffer overflow and a crash. An unauthenticated attacker can trigger this remotely via malformed TLS Application Data records.

CVE-2026-0819 Alta · 7.1 CWE-787 19/03/2026

Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes

A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd->signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7->signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.

CVE-2025-13912 Baixa · 1.0 CWE-203 11/12/2025

Potential non-constant time compiled code with Clang LLVM

Multiple constant-time implementations in wolfSSL before version 5.8.4 may be transformed into non-constant-time binary by LLVM optimizations, which can potentially result in observable timing discrepancies and lead to information disclosure through timing side-channel attacks.

CVE-2025-12889 Média · 5.4 CWE-20 21/11/2025

TLS 1.2 Client Can Downgrade Digest Used

With TLS 1.2 connections a client can use any digest, specifically a weaker digest that is supported, rather than those in the CertificateRequest.

CVE-2025-12888 Alta · 7.5 CWE-203 21/11/2025

Constant Time Issue with Xtensa-based ESP32 and X22519

Vulnerability in X25519 constant-time cryptographic implementations due to timing side channels introduced by compiler optimizations and CPU architecture limitations, specifically with the Xtensa-based ESP32 chips. If targeting Xtensa it is recommended to use the low memory implementations of X25519, which is now turned on as the default for Xtensa.

CVE-2025-11936 Média · 5.3 CWE-20 21/11/2025

Potential DoS Vulnerability through Multiple KeyShareEntry with Same Group in TLS 1.3 ClientHello

Improper input validation in the TLS 1.3 KeyShareEntry parsing in wolfSSL v5.8.2 on multiple platforms allows a remote unauthenticated attacker to cause a denial-of-service by sending a crafted ClientHello message containing duplicate KeyShareEntry values for the same supported group, leading to excessive CPU and memory consumption during ClientHello processing.

CVE-2025-11934 Baixa · 2.7 CWE-20 21/11/2025

Improper Validation of Signature Algorithm Used in TLS 1.3 CertificateVerify

Improper input validation in the TLS 1.3 CertificateVerify signature algorithm negotiation in wolfSSL 5.8.2 and earlier on multiple platforms allows for downgrading the signature algorithm used. For example when a client sends ECDSA P521 as the supported signature algorithm the server previously could respond as ECDSA P256 being the accepted signature algorithm and the connection would continue with using ECDSA P256, if the client supports ECDSA P256.

CVE-2025-11932 Média · 4.3 CWE-203 21/11/2025

Timing Side-Channel in PSK Binder Verification

The server previously verified the TLS 1.3 PSK binder using a non-constant time method which could potentially leak information about the PSK binder

CVE-2025-11933 Média · 6.5 CWE-20 21/11/2025

DoS Vulnerability in wolfSSL TLS 1.3 CKS Extension

Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.

CVE-2025-11931 Alta · 8.2 CWE-191 21/11/2025

Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt

Integer Underflow Leads to Out-of-Bounds Access in XChaCha20-Poly1305 Decrypt. This issue is hit specifically with a call to the function wc_XChaCha20Poly1305_Decrypt() which is not used with TLS connections, only from direct calls from an application.

CVE-2025-11935 Alta · 7.5 CWE-326 21/11/2025

Forward Secrecy Violation in WolfSSL TLS 1.3

With TLS 1.3 pre-shared key (PSK) a malicious or faulty server could ignore the request for PFS (perfect forward secrecy) and the client would continue on with the connection using PSK without PFS. This happened when a server responded to a ClientHello containing psk_dhe_ke without a key_share extension. The re-use of an authenticated PSK connection that on the clients side unexpectedly did not have PFS, reduces the security of the connection.