wolfSSL Security Vulnerabilities

The SSL protocol, along with the more recent TLS 1.2 protocol, are both well documented and under constant scrutiny by the top experts in security and cryptography. SSL was quickly adopted as a standard world wide. SSL and TLS together secure communications between billions of computers, servers, Internet of Things (IoT) devices, and embedded systems. The security provided by an SSL/TLS Library depends on the underlying strength of its cryptography which is used to encrypt communications.

INFO	CVE ID	SEVERITY	DESCRIPTION	TIME TO FIX	FIXED IN VERSION
LINK	CVE-2022-42905	Medium	In the case that the WOLFSSL_CALLBACKS macro is set when building wolfSSL, there is a potential heap over read of 5 bytes when handling TLS 1.3 client connections. This heap over read is limited to wolfSSL builds explicitly setting the macro WOLFSSL_CALLBACKS, the feature does not get turned on by any other build options. The macro WOLFSSL_CALLBACKS is intended for debug use only, but if having it enabled in production, users are recommended to disable WOLFSSL_CALLBACKS. Users enabling WOLFSSL_CALLBACKS are recommended to update their version of wolfSSL. Thanks to Lucca Hirschi and Steve Kremer from LORIA, Inria and Max Ammann from Trail of Bits for finding and reporting the bug with the tlspuffin tool developed partly at LORIA and Trail of Bits.	1 day	5.5.2
LINK	CVE-2022-39173	Medium	Denial of service attack and buffer overflow against TLS 1.3 servers using session ticket resumption. When built with --enable-session-ticket and making use of TLS 1.3 server code in wolfSSL, there is the possibility of a malicious client to craft a malformed second ClientHello packet that causes the server to crash. This issue is limited to when using both --enable-session-ticket and TLS 1.3 on the server side. Users with TLS 1.3 servers, and having --enable-session-ticket, should update to the latest version of wolfSSL. Thanks to Max at Trail of Bits for the report, found by Lucca Hirschi from LORIA, Inria, France with the tlspuffin tool developed partly at LORIA and Trail of Bits.	0 days	5.5.1
LINK	CVE-2022-42961	Low	Fault injection attack on RAM via Rowhammer leads to ECDSA key disclosure. Users doing operations with private ECC keys such as server side TLS connections and creating ECC signatures, who also have hardware that could be targeted with a sophisticated Rowhammer attack should update the version of wolfSSL and compile using the macro WOLFSSL_CHECK_SIG_FAULTS. Thanks to Yarkin Doroz, Berk Sunar, Koksal Must, Caner Tol, and Kristi Rahman all affiliated with the Vernam Applied Cryptography and Cybersecurity Lab at Worcester Polytechnic Institute for the report.	5 days	5.5.0
LINK	CVE-2022-38153	Low	In wolfSSL version 5.3.0 if compiled with --enable-session-ticket and the client has non-empty session cache, with TLS 1.2 there is the possibility of a man in the middle passing a large session ticket to the client and causing a crash due to an invalid free. There is also the potential for a malicious TLS 1.3 server to crash a client in a similar manner except in TLS 1.3 it is not susceptible to a man in the middle attack. Users on the client side with –enable-session-ticket compiled in and using wolfSSL version 5.3.0 should update their version of wolfSSL. Thanks to Max at Trail of Bits for the report and "LORIA, INRIA, France" for research on tlspuffin.	5 days	5.5.0
LINK	CVE-2022-38152	Low	If using wolfSSL_clear to reset a WOLFSSL object (vs the normal wolfSSL_free/wolfSSL_new) it can result in runtime issues. This exists with builds using the wolfSSL compatibility layer (--enable-opnesslextra) and only when the application is making use of wolfSSL_clear instead of SSL_free/SSL_new. In the case of a TLS 1.3 resumption, after continuing to use the WOLFSSH object after having called wolfSSL_clear, an application could crash. It is suggested that users calling wolfSSL_clear update the version of wolfSSL used. Thanks to Max at Trail of Bits for the report and "LORIA, INRIA, France" for research on tlspuffin.	2 days	5.5.0
LINK	N/A	Medium	Potential DoS attack on DTLS 1.2. In the case of receiving a malicious plaintext handshake message at epoch 0 the connection will enter an error state reporting a duplicate message. This affects both server and client side. Users that have DTLS enabled and in use should update their version of wolfSSL to mitigate the potential for a DoS attack.	0 days	5.5.0
LINK	CVE-2022-34293	High	Potential for DTLS DoS attack. In wolfSSL versions before 5.4.0 the return-routability check is wrongly skipped in a specific edge case. The check on the return-routability is there for stopping attacks that either consume excessive resources on the server, or try to use the server as an amplifier sending an excessive amount of messages to a victim IP. If using DTLS 1.0/1.2 on the server side users should update to avoid the potential DoS attack.	4 days	5.4.0
LINK	N/A	Medium	Ciphertext side channel attack on ECC and DH operations. Users on systems where rogue agents can monitor memory use should update the version of wolfSSL and change private ECC keys. Thanks to Sen Deng from Southern University of Science and Technology (SUSTech) for the report.	6 days	5.4.0
LINK	CVE-2022-25640	High	A TLS v1.3 server who requires mutual authentication can be bypassed. If a malicious client does not send the certificate_verify message a client can connect without presenting a certificate even if the server requires one. Thank you to Aina Toky Rasoamanana and Olivier Levillain of Télécom SudParis.	11 days	5.2.0
LINK	CVE-2022-25638	High	A TLS v1.3 client attempting to authenticate a TLS v1.3 server can have its certificate check bypassed. If the sig_algo in the certificate_verify message is different than the certificate message checking may be bypassed. Thank you to Aina Toky Rasoamanana and Olivier Levillain of Télécom SudParis.	6 days	5.2.0
LINK	CVE-2022-23408	High	In connections using AES-CBC or DES3 with TLS/DTLS 1.2 or 1.1 the IV being used is not random. Users using wolfSSL version 5.0.0 or 5.1.0 doing TLS/DTLS 1.2 or 1.1 connections, without AEAD only, should update the version of wolfSSL used.	0 days	5.1.1
LINK	CVE-2020-12966 CVE-2021-46744	Medium	Public disclosure of a side channel vulnerability that has been fixed since wolfSSL version 5.1.0. When running on AMD there is the potential to leak private key information with ECDSA operations due to a ciphertext side channel attack. Users on AMD doing ECDSA operations with wolfSSL versions less than 5.1.0 should update their wolfSSL version used. Thanks to professor Yinqian Zhang from Southern University of Science and Technology (SUSTech), his Ph.D. student Mengyuan Li from The Ohio State University, and his M.S students Sen Deng and Yining Tang from SUStech along with other collaborators; Luca Wilke, Jan Wichelmann and Professor Thomas Eisenbarth from the University of Lubeck, Professor Shuai Wang from Hong Kong University of Science and Technology, Professor Radu Teodorescu from The Ohio State University, Huibo Wang, Kang Li and Yueqiang Cheng from Baidu Security and Shoumeng Yang from Ant Financial Services Group.	Fixed 107 days prior to CVE issuance.	5.1.0
LINK	CVE-2021-44718	Low	Potential for DoS attack on a wolfSSL client due to processing hello packets of the incorrect side. This affects only connections using TLS v1.2 or less that have also been compromised by a man in the middle attack. Thanks to James Henderson, Mathy Vanhoef, Chris M. Stone, Sam L. Thomas, Nicolas Bailleut, and Tom Chothia (University of Birmingham, KU Leuven, ENS Rennes for the report.	0 days	5.1.0
LINK	N/A	Low	Client side session resumption issue once the session resumption cache has been filled up. The hijacking of a session resumption has been demonstrated so far with only non verified peer connections. That is where the client is not verifying the server’s CA that it is connecting to. There is the potential though for other cases involving proxies that are verifying the server to be at risk, if using wolfSSL in a case involving proxies use wolfSSL_get1_session and then wolfSSL_SESSION_free when done where possible. If not adding in the session get/free function calls we recommend that users of wolfSSL that are resuming sessions update to the latest version (wolfSSL version 5.1.0 or later). Thanks to the UK's National Cyber Security Centre (NCSC) for the report.	6 days	5.1.0
LINK	N/A	Low	Hang with DSA signature creation when a specific q value is used in a maliciously crafted key. If a DSA key with an invalid q value of either 1 or 0 was decoded and used for creating a signature, it would result in a hang in wolfSSL. Users that are creating signatures with DSA and are using keys supplied from an outside source are affected.	3 days	5.0.0
LINK	N/A	Low	Issue with incorrectly validating a certificate that has multiple subject alternative names when given a name constraint. In the case where more than one subject alternative name is used in the certificate, previous versions of wolfSSL could incorrectly validate the certificate. Users verifying certificates with multiple alternative names and name constraints, are recommended to either use the certificate verify callback to check for this case or update the version of wolfSSL used. Thanks to Luiz Angelo Daros de Luca for the report.	2 days	5.0.0
LINK	CVE-2021-38597	High	OCSP verification issue when response is for a certificate with no relation to the chain in question BUT that response contains the NoCheck extension which effectively disables ALL verification of that one cert. Users who should upgrade to 4.8.1 are TLS client users doing OCSP, TLS server users doing mutual auth with OCSP, and CertManager users doing OCSP independent of TLS. Thanks to Jan Nauber, Marco Smeets, Werner Rueschenbaum and Alissa Kim for the report.	8 days	4.8.1
LINK	N/A	Low	OCSP request/response verification issue. In the case that the serial number in the OCSP request differs from the serial number in the OCSP response the error from the comparison was not resulting in a failed verification. We recommend users that have wolfSSL version 4.6.0 and 4.7.0 with OCSP enabled update their version of wolfSSL. Version 4.5.0 and earlier are not affected by this report. Thanks to Rainer, Roee, Barak, Hila and Shoshi (from Cymotive and CARIAD) for the report.	2 days	4.8.0
LINK	CVE-2021-3336	High	In earlier versions of wolfSSL there exists a potential man in the middle attack on TLS 1.3 clients. Malicious attackers with a privileged network position can impersonate TLS 1.3 servers and bypass authentication. Users that have applications with client side code and have TLS 1.3 turned on, should update to the latest version of wolfSSL. Users that do not have TLS 1.3 turned on, or that are server side only, are NOT affected by this report. For the code change see https://github.com/wolfSSL/wolfssl/pull/3676. Thanks to Aina Toky Rasoamanana and Olivier Levillain from Télécom SudParis for the report.	Fixed 12 days prior to CVE issuance	4.7.0
LINK	N/A	Low	In the case of using custom ECC curves there is the potential for a crafted compressed ECC key that has a custom prime value to cause a hang when imported. This only affects applications that are loading in ECC keys with wolfSSL builds that have compressed ECC keys and custom ECC curves enabled.	1 day	4.7.0
LINK	N/A	Low	With TLS 1.3 authenticated-only ciphers a section of the server hello could contain 16 bytes of uninitialized data when sent to the connected peer. This affects only a specific build of wolfSSL with TLS 1.3 early data enabled and using authenticated-only ciphers with TLS 1.3.	12 days	4.7.0
LINK	CVE-2021-24116	Low	Side-Channel cache look up vulnerability in base64 PEM decoding for versions of wolfSSL 4.5.0 and earlier. Versions 4.6.0 and up contain a fix and do not need to be updated for this report. If decoding a PEM format private key using version 4.5.0 and older of wolfSSL then we recommend updating the version of wolfSSL used. Thanks to Florian Sieck, Jan Wichelmann, Sebastian Berndt and Thomas Eisenbarth for the report.	Fixed 7 months prior to CVE issuance	4.6.0
LINK	CVE-2020-24613	High	In wolfSSL versions prior to 4.5.0 there exists a potential man in the middle attack on TLS 1.3 clients. Malicious attackers with a privileged network position can impersonate TLS 1.3 servers and bypass authentication. Users that have applications with client side code and have TLS 1.3 turned on, should update to the latest version of wolfSSL. Users that do not have TLS 1.3 turned on, or that are server side only, are NOT affected by this report. Thanks to Gerald Doussot from NCC group for the report.	2 days	4.5.0
LINK	CVE-2020-12457	Low	In wolfSSL versions prior to 4.5.0, a denial of service attack on TLS 1.3 servers from repetitively sending ChangeCipherSpecs messages is possible. This denial of service results from the relatively low effort of sending a ChangeCipherSpecs message versus the effort of the server to process that message. Users with TLS 1.3 servers are recommended to update to the most recent version of wolfSSL which limits the number of TLS 1.3 ChangeCipherSpecs that can be received in order to avoid this DoS attack. CVE-2020-12457 was reserved for the report. Thanks to Lenny Wang of Tencent Security Xuanwu LAB.	Fixed 114 days prior to CVE issuance	4.5.0
LINK	CVE-2020-15309	Low	wolfSSL versions prior to 4.5.0 included a potential cache timing attack on public key operations in builds that are not using SP (single precision). Users that have a system where malicious agents could execute code on the system, are not using the SP build with wolfSSL, and are doing private key operations on the system (such as signing with a private key) are recommended to regenerate private keys and update to the most recent version of wolfSSL. CVE-2020-15309 is reserved for this issue. Thanks to Ida Bruhns from Universität zu Lübeck for the report.	Fixed 57 days prior to CVE issuance	4.5.0
LINK	N/A	Low	In wolfSSL versions prior to 4.5.0, when using SGX with EC scalar multiplication the possibility of side-channel attacks are present. To mitigate the risk of side channel attacks wolfSSL’s single precision EC operations should be used instead. Release 4.5.0 turns this on be default now with SGX builds and in previous versions of wolfSSL this can be turned on by using the WOLFSSL_SP macros. Thank you to Alejandro Cabrera Aldaya, Cesar Pereida García and Billy Bob Brumley from the Network and Information Security Group (NISEC) at Tampere University for the report.	1 day	4.5.0
LINK	N/A	High	wolfSSL versions prior to 4.5.0 may leak the private key in the case that PEM format private keys are bundled in with PEM certificates into a single file. This is due to the misclassification of certificate type versus private key type when parsing through the PEM file. To be affected, wolfSSL would need to have been built with OPENSSL_EXTRA (--enable-opensslextra). Some build variants such as --enable-all and --enable-opensslall also turn on this code path, checking wolfssl/options.h for OPENSSL_EXTRA will show if the macro was used with the build. If having built with the opensslextra enable option and having placed PEM certificates with PEM private keys in the same file when loading up the certificate file, then we recommend updating wolfSSL for this use case and also recommend regenerating any private keys in the file.	1 day	4.5.0
LINK	N/A	Low	In wolfSSL versions prior to 4.5.0, during the handshake, clear application_data messages in epoch 0 are processed and returned to the application. Fixed by dropping received application_data messages in epoch 0. Thank you to Paul Fiterau of Uppsala University and Robert Merget of Ruhr-University Bochum for the report.	0 days	4.5.0
LINK	CVE-2020-11713	Low	wolfSSL versions prior to 4.4.0 have mulmod code in wc_ecc_mulmod_ex in ecc.c that does not properly resist timing side-channel attacks. Version 4.4.0 fixes this to be constant time and cache resistant. Thank you to Pietro Borrello at Sapienza University of Rome.	Fixed 4 days prior to CVE issuance	4.4.0
LINK	CVE-2020-11735	Low	wolfSSL versions prior to 4.4.0 using fast math do not use a constant-time modular inverse when mapping to affine coordinates. Version 4.4.0 uses a constant time modular inverse when mapping to affine when operation involves a private key - keygen, calc shared secret, sign. Thank you to Alejandro Cabrera Aldaya, Cesar Pereida García and Billy Bob Brumley from the Network and Information Security Group (NISEC) at Tampere University for the report.	Fixed 36 days prior to CVE issuance	4.4.0
	CVE-2019-18840	High	In wolfSSL 4.1.0 through 4.2.0c, there are missing sanity checks of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically, there is a one-byte heap-based buffer overflow inside the DecodedCert structure in GetName in wolfcrypt/src/asn.c because the domain name location index is mishandled. Because a pointer is overwritten, there is an invalid free	0 days	4.3.0
LINK	N/A	Low	In wolfSSL versions prior to 4.2.0, there is a potential program hang when ocspstapling2 is enabled. This is a moderate level fix that affects users who have ocspstapling2 enabled(off by default) and are on the server side. In parsing a CSR2 (Certificate Status Request v2 ) on the server side, there was the potential for a malformed extension to cause a program hang. Discovered by Robert Hoerr.	5 days	4.2.0
LINK	CVE-2019-16748	High	In wolfSSL through 4.1.0, there is a missing sanity check of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically, there is a one-byte heap-based buffer over-read in CheckCertSignature_ex in wolfcrypt/src/asn.c.	1 days	4.2.0
LINK	CVE-2019-15651	High	wolfSSL 4.1.0 has a one-byte heap-based buffer over-read in DecodeCertExtensions in wolfcrypt/src/asn.c because reading the ASN_BOOLEAN byte is mishandled for a crafted DER certificate in GetLength_ex.	1 days	4.2.0
LINK	N/A	Low	wolfSSL versions before 4.2.0 have potential for an invalid read when TLS 1.3 and pre-shared keys is enabled. Users without TLS 1.3 enabled are unaffected. Users with TLS 1.3 enabled and HAVE_SESSION_TICKET defined or NO_PSK not defined should update wolfSSL versions. Discovered by Robert Hoerr.	0 days	4.2.0
LINK	CVE-2019-14317	Low	Versions of wolfSSL before 4.2.0 are vulnerable to DSA operations involving an attack on recovering DSA private keys. This affects users that have DSA enabled and are performing DSA operations (off by default). ECDSA is NOT affected by this and TLS code is NOT affected by this issue. Discovered by Ján Jančár at Masaryk University.	0 days	4.2.0
LINK	CVE-2019-13628	Medium	Versions of wolfSSL before 4.1.0 are vulnerable to the potential leak of nonce sizes when performing ECDSA signing operations. The leak is considered to be difficult to exploit but it could potentially be used maliciously to perform a lattice based timing attack against previous wolfSSL versions. Discovered by Ján Jančár at Masaryk University.	5 days	4.1.0
LINK	CVE-2019-11873	High	In wolfSSL version 4.0.0, there is a potential buffer overflow case with the TLSv1.3 PSK extension parsing. This affects users that are enabling TLSv1.3 (--enable-tls13). Discovered by Robert Hoerr.	0 days	4.1.0
LINK	CVE-2018-16870	Medium	Versions of wolfSSL prior to 3.15.7 are vulnerable to a new variant of the Bleichenbacher attack to perform downgrade attacks against TLS, which may lead to leakage of sensible data.	0 days	3.15.7
LINK	CVE-2018-12436	Medium	Versions of wolfSSL up to and including 3.15.0 are vulnerable to a Key Extraction Side Channel Attack. A patch (wolfssl-3.15.1.patch) is available for download now on our website and a full release will be available next week containing the patch.	0 days	3.15.3
LINK	CVE-2017-13099	Medium	Versions of wolfSSL up to 3.12.2 have a weak Bleichenbacher vulnerability with suites that use an RSA-encrypted premaster secret. Discovered by Hanno Böck, Juraj Somorovsky, Craig Young.	9 days	3.13.0
LINK	CVE-2017-2800	Critical	Versions of wolfSSL before 3.11.0 have a possible out-of-bounds write by one from a crafted certificate being passed to the function wolfSSL_X509_NAME_get_text_by_NID. Discovered by Aleksandar Nikolic of Cisco Talos.	Fixed 20 days prior to CVE issuance	3.11.0
LINK	CVE-2017-8855	High	In versions of wolfSSL before 3.11.0 there are cases where a malformed DH key is not rejected by the function wc_DhAgree. Thanks to Yueh-Hsun Lin and Peng Li at KNOX Security at Samsung Research America.	Fixed 5 days prior to CVE issuance	3.11.0
LINK	CVE-2017-8854	High	Versions of wolfSSL before 3.10.2 have a possible out-of-bounds memory access when loading crafted DH parameters. Thanks to Yueh-Hsun Lin and Peng Li at KNOX Security at Samsung Research America.	Fixed 88 days prior to CVE issuance	3.10.2
LINK	CVE-2017-6076	Medium	In versions of wolfSSL before 3.10.2 the software implementation makes it easier to extract RSA key information for a malicious user who has access to view the cache on a machine.	Fixed 13 days prior to CVE issuance	3.10.2
LINK	CVE-2016-7440	Medium	Software AES table lookups do not properly consider cache-bank access times	Fixed 81 days prior to CVE issuance	3.9.10
LINK	CVE-2016-7439	Medium	Software RSA does not properly consider cache-bank monitoring	Fixed 81 days prior to CVE issuance	3.9.10
LINK	CVE-2016-7438	Medium	Software ECC does not properly consider cache-bank monitoring	Fixed 81 days prior to CVE issuance	3.9.10
LINK	CVE-2015-6925	High	Potential DOS attack when using DTLS on the server side	Fixed 127 days prior to CVE issuance	3.6.8
LINK	CVE-2015-7744	Medium	TLS servers using RSA with ephemeral keys may leak key bits on signature faults	Fixed 127 days prior to CVE issuance	3.6.8
LINK	CVE-2014-2903	Medium	Server certificate not authorized for use in SSL/TLS handshake. CyaSSL does not check the key usage extension in leaf certificates.	Fixed 13 days prior to issuance	2.9.4
LINK	CVE-2014-2900	Medium	Unknown critical certificate extension allowed	Fixed 13 days prior to issuance	2.9.4
LINK	CVE-2014-2899	Medium	NULL pointer dereference on peer cert request after certificate parsing failure	Fixed 13 days prior to issuance	2.9.4
LINK	CVE-2014-2898	Low	Out of bounds read on repeated calls to CyaSSL_read(), memory access error.	Fixed 13 days prior to issuance	2.9.4
LINK	CVE-2014-2897	High	Out of bounds read, SSL 3.0 HMAC doesn't check padding length for verify failure	Fixed 13 days prior to issuance	2.9.4
LINK	CVE-2014-2896	N/A	Memory corruption, possible out of bounds read on length check in DoAlert()	Fixed 13 days prior to issuance	2.9.4

As researchers and security professionals release new attacks against SSL/TLS protocol versions, algorithms, or cryptographic modes, we want to keep our users informed if wolfSSL is vulnerable or safe to such attacks.

DATE	NAME	SEVERITY	WOLFSSL AFFECTED	ADDRESSED
09.09.2020	Raccoon Attack	Low	NO	N/A
12.08.2017	The ROBOT Attack	Medium	YES	YES
08.24.2016	SWEET32 Attack	TLS & SSH - High OpenVPN - Medium	YES	YES
03.01.2016	DROWN Attack	Medium	NO	N/A
01.07.2016	SLOTH Attack	Medium	NO	N/A
08.11.2015	Pandora's Box Attack	N/A	NO	N/A
07.09.2015	Logjam Attack	Critical	NO	N/A
03.30.2015	Bar Mitzvah Attack	Medium	YES	YES
03.04.2015	FREAK Attack	Medium for all implementations	YES	N/A
12.12.2014	POODLE Bites Again	Medium	NO	N/A
10.14.2014	POODLE: Padding Oracle On Downgraded Legacy Encryption	Medium	YES	YES
04.09.2014	Heartbleed Bug	Medium	NO	N/A
02.05.2014	Lucky 13 Attack	Low	YES	YES
09.24.2012	CRIME Attack	Low	YES	YES
05.13.2011	BEAST Attack	Medium	YES	YES

The SSH protocol is well documented and under constant scrutiny by the top experts in security and cryptography. SSH was quickly adopted as a standard world wide. SSH secures connections between billions of users to their shell accounts, and allows for secure file transfers between billions of computers, servers, Internet of Things (IoT) devices, and embedded systems. The security provided by an SSH Library depends on the underlying strength of its cryptography which is used to encrypt communications.

INFO	CVE ID	SEVERITY	DESCRIPTION	TIME TO FIX	FIXED IN VERSION
LINK	N/A	Low	When processing SFTP messages, wolfSSH isn't checking data lengths against the size of the message and is potentially under-allocating, over-reading, and over-writing buffers.	4 days	1.4.8

Known wolfSSL Vulnerabilities

Known SSL/TLS Protocol Attacks

Known wolfSSH Vulnerabilities

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