The Montgomery ladder implementation in OpenSSL through 1.0.0l does not ensure that certain swap operations have a constant-time behavior, which makes it easier for local users to obtain ECDSA nonces via a FLUSH+RELOAD cache side-channel attack.

OpenSSL before 0.9.8k on WIN64 and certain other platforms does not properly handle a malformed ASN.1 structure, which allows remote attackers to cause a denial of service (invalid memory access and application crash) by placing this structure in the public key of a certificate, as demonstrated by an RSA public key.

Bodo Möller, Thai Duong and Krzysztof Kotowicz of Google discovered a flaw in the design of SSL version 3.0 that would allow an attacker to calculate the plaintext of secure connections, allowing, for example, secure HTTP cookies to be stolen.

References: http://googleonlinesecurity.blogspot.com/2014/10/this-poodle-bites-exploiting-ssl-30.html https://www.openssl.org/~bodo/ssl-poodle.pdf

If an X.509 certificate has a malformed IPAddressFamily extension, OpenSSL could do a one-byte buffer overread. The most likely result would be an erroneous display of the certificate in text format.

External References:

https://www.openssl.org/news/secadv/20170828.txt

References:

https://github.com/openssl/openssl/pull/4276

A denial of service flaw was found in OpenSSL 0.9.8, 1.0.1, 1.0.2 through 1.0.2h, and 1.1.0 in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections from other clients.

As per the upstream advisory:

By sending an invalid DTLS handshake to an OpenSSL DTLS client, the code can be made to recurse, eventually crashing in a DoS attack.

Only applications using OpenSSL as a DTLS client are affected.

OpenSSL 0.9.8 DTLS users should upgrade to 0.9.8za OpenSSL 1.0.0 DTLS users should upgrade to 1.0.0m. OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1h. .

Acknowledgements:

Red Hat would like to thank the OpenSSL project for reporting this issue. Upstream acknowledges Imre Rad of Search-Lab as the original reporter of this issue.

A flaw in how TLS/DTLS, when CBC-mode encryption is used, communicates was reported. This vulnerability can allow for a Man-in-the-Middle attacker to recover plaintext from a TLS/DTLS connection, when CBC-mode encryption is used.

This flaw is in the TLS specification, and not a bug in a specific implementation (as such, it affects nearly all implementations). As such, it affects all TLS and DTLS implementations that are compliant with TLS 1.1 or 1.2, or with DTLS 1.0 or 1.2. It also applies to implementations of SSL 3.0 and TLS 1.0 that incorporate countermeasures to deal with previous padding oracle attacks. All TLS/DTLS ciphersuites that include CBC-mode encryption are potentially vulnerable.

The paper indicates that with OpenSSL, a full plaintext recovery attack is possible, and with GnuTLS, a partial plaintext recovery is possible (recovering up to 4 bits of the last byte in any block of plaintext).

To perform a successful attack, when TLS is used, a large number of TLS sessions are required (target plaintext must be sent repeatedly in the same position in the plaintext stream across the sessions). For DTLS, a successful attack can be carried out in a single session. The attacker must also be located close to the machine being attacked.

Further details are noted in the paper.

Current status of fixes in various implementations:

OpenSSL has a patch in development NSS has a patch in development GnuTLS is fixed in versions 2.12.23, 3.0.28, and 3.1.7 PolarSSL is fixed in version 1.2.5 BouncyCastle has a patch that will be included in the forthcoming 1.48 version

Full paper:

http://www.isg.rhul.ac.uk/tls/TLStiming.pdf

External References:

http://www.isg.rhul.ac.uk/tls/ http://www.openssl.org/news/secadv20130205.txt https://polarssl.org/tech-updates/releases/polarssl-1.2.5-released

As per the upstream advisory:

A buffer overrun attack can be triggered by sending invalid DTLS fragments to an OpenSSL DTLS client or server. This is potentially exploitable to run arbitrary code on a vulnerable client or server.

Only applications using OpenSSL as a DTLS client or server affected.

OpenSSL 0.9.8 DTLS users should upgrade to 0.9.8za OpenSSL 1.0.0 DTLS users should upgrade to 1.0.0m. OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1h.

Acknowledgements:

Red Hat would like to thank the OpenSSL project for reporting this issue. Upstream acknowledges Jüri Aedla as the original reporter of this issue.

From the upstream advisory [1]:

nvalid ASN1 module definition for CMS. =======================================

CMS structures containing OriginatorInfo are mishandled this can write to invalid memory addresses or free up memory twice (CVE-2010-0742).

This bug is only present in the CMS code: the older PKCS#7 code is not affected.

CMS is only present in OpenSSL 0.9.8h and later where it is disabled by default and 1.0.0 where it is enabled by default.

Users of OpenSSL CMS code should update to 0.9.8o or 1.0.0a which contains a patch to correct this issue.

Thanks to Ronald Moesbergen for reporting this issue.

This has been corrected upstream via:

http://cvs.openssl.org/chngview?cn=19693

[1] http://www.openssl.org/news/secadv20100601.txt

The ksslkeytabisavailable function in ssl/kssl.c in OpenSSL before 0.9.8n, when Kerberos is enabled but Kerberos configuration files cannot be opened, does not check a certain return value, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via SSL cipher negotiation, as demonstrated by a chroot installation of Dovecot or stunnel without Kerberos configuration files inside the chroot.

OpenSSL before 0.9.8m does not check for a NULL return value from bnwexpand function calls in (1) crypto/bn/bndiv.c, (2) crypto/bn/bngf2m.c, (3) crypto/ec/ec2smpl.c, and (4) engines/eubsec.c, which has unspecified impact and context-dependent attack vectors.

The getserverhello function in the SSLv2 client code in OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier versions allows remote servers to cause a denial of service (client crash) via unknown vectors that trigger a null pointer dereference.

Buffer overflow in the SSLgetsharedciphers function in OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier versions has unspecified impact and remote attack vectors involving a long list of ciphers.

OpenSSL 0.9.7 before 0.9.7l and 0.9.8 before 0.9.8d allows remote attackers to cause a denial of service (infinite loop and memory consumption) via malformed ASN.1 structures that trigger an improperly handled error condition.

OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier versions allows attackers to cause a denial of service (CPU consumption) via parasitic public keys with large (1) "public exponent" or (2) "public modulus" values in X.509 certificates that require extra time to process when using RSA signature verification.

The SSL/TLS server implementation in OpenSSL 0.9.7 before 0.9.7h and 0.9.8 before 0.9.8a, when using the SSLOPMSIESSLV2RSAPADDING option, disables a verification step that is required for preventing protocol version rollback attacks, which allows remote attackers to force a client and server to use a weaker protocol than needed via a man-in-the-middle attack.

The mimehdrcmp function in crypto/asn1/asnmime.c in OpenSSL 0.9.8t and earlier allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted S/MIME message.

OpenSSL before 0.9.7, 0.9.7 before 0.9.7k, and 0.9.8 before 0.9.8c, when using an RSA key with exponent 3, removes PKCS-1 padding before generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by that RSA key and prevents OpenSSL from correctly verifying X.509 and other certificates that use PKCS #1.

Off-by-one error in the SSLgetsharedciphers function in OpenSSL 0.9.7 up to 0.9.7l, and 0.9.8 up to 0.9.8f, might allow remote attackers to execute arbitrary code via a crafted packet that triggers a one-byte buffer underflow. NOTE: this issue was introduced as a result of a fix for CVE-2006-3738. As of 20071012, it is unknown whether code execution is possible.

Off-by-one error in the DTLS implementation in OpenSSL 0.9.8 before 0.9.8f allows remote attackers to execute arbitrary code via unspecified vectors.

Multiple memory leaks in the dtls1processoutofseqmessage function in ssl/d1both.c in OpenSSL 0.9.8k and earlier 0.9.8 versions allow remote attackers to cause a denial of service (memory consumption) via DTLS records that (1) are duplicates or (2) have sequence numbers much greater than current sequence numbers, aka "DTLS fragment handling memory leak."

The dtls1bufferrecord function in ssl/d1pkt.c in OpenSSL 0.9.8k and earlier 0.9.8 versions allows remote attackers to cause a denial of service (memory consumption) via a large series of "future epoch" DTLS records that are buffered in a queue, aka "DTLS record buffer limitation bug."

OpenSSL before 1.0.0c, when J-PAKE is enabled, does not properly validate the public parameters in the J-PAKE protocol, which allows remote attackers to bypass the need for knowledge of the shared secret, and successfully authenticate, by sending crafted values in each round of the protocol.

Double free vulnerability in the ssl3getkeyexchange function in the OpenSSL client (ssl/s3clnt.c) in OpenSSL 1.0.0a, 0.9.8, 0.9.7, and possibly other versions, when using ECDH, allows context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted private key with an invalid prime. NOTE: some sources refer to this as a use-after-free issue.

The GOST ENGINE in OpenSSL before 1.0.0f does not properly handle invalid parameters for the GOST block cipher, which allows remote attackers to cause a denial of service (daemon crash) via crafted data from a TLS client.