crypto/bn/bn_nist.c in OpenSSL before 0.9.8h on 32-bit platforms, as used in stunnel and other products, in certain circumstances involving ECDH or ECDHE cipher suites, uses an incorrect modular reduction algorithm in its implementation of the P-256 and P-384 NIST elliptic curves, which allows remote attackers to obtain the private key of a TLS server via multiple handshake attempts.

It was discovered that the elliptic curve cryptography (ECC) subsystem in OpenSSL, when using the Elliptic Curve Digital Signature Algorithm (ECDSA) for the ECDHE_ECDSA cipher suite, did not properly implement curves over binary fields. This could allow an attacker to determine private keys via a timing attack. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04. (CVE-2011-1945)

Adam Langley discovered that the ephemeral Elliptic Curve Diffie-Hellman (ECDH) functionality in OpenSSL did not ensure thread safety while processing handshake messages from clients. This could allow a remote attacker to cause a denial of service via out-of-order messages that violate the TLS protocol. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04.
(CVE-2011-3210)

Nadhem Alfardan and Kenny Paterson discovered that the Datagram Transport Layer Security (DTLS) implementation in OpenSSL performed a MAC check only if certain padding is valid. This could allow a remote attacker to recover plaintext. (CVE-2011-4108)

Antonio Martin discovered that a flaw existed in the fix to address CVE-2011-4108, the DTLS MAC check failure. This could allow a remote attacker to cause a denial of service. (CVE-2012-0050)

Ben Laurie discovered a double free vulnerability in OpenSSL that could be triggered when the X509_V_FLAG_POLICY_CHECK flag is enabled.
This could allow a remote attacker to cause a denial of service. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04. (CVE-2011-4109)

It was discovered that OpenSSL, in certain circumstances involving ECDH or ECDHE cipher suites, used an incorrect modular reduction algorithm in its implementation of the P-256 and P-384 NIST elliptic curves. This could allow a remote attacker to obtain the private key of a TLS server via multiple handshake attempts. This issue only affected Ubuntu 8.04 LTS. (CVE-2011-4354)

Adam Langley discovered that the SSL 3.0 implementation in OpenSSL did not properly initialize data structures for block cipher padding. This could allow a remote attacker to obtain sensitive information.
(CVE-2011-4576)

Andrew Chi discovered that OpenSSL, when RFC 3779 support is enabled, could trigger an assert when handling an X.509 certificate containing certificate-extension data associated with IP address blocks or Autonomous System (AS) identifiers. This could allow a remote attacker to cause a denial of service. (CVE-2011-4577)

Adam Langley discovered that the Server Gated Cryptography (SGC) implementation in OpenSSL did not properly handle handshake restarts.
This could allow a remote attacker to cause a denial of service.
(CVE-2011-4619)

Andrey Kulikov discovered that the GOST block cipher engine in OpenSSL did not properly handle invalid parameters. This could allow a remote attacker to cause a denial of service via crafted data from a TLS client. This issue only affected Ubuntu 11.10. (CVE-2012-0027).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Several vulnerabilities were discovered in OpenSSL, an implementation of TLS and related protocols. The Common Vulnerabilities and Exposures project identifies the following vulnerabilities :

  - CVE-2011-4108     The DTLS implementation performs a MAC check only if     certain padding is valid, which makes it easier for     remote attackers to recover plaintext via a padding     oracle attack.

  - CVE-2011-4109     A double free vulnerability when     X509_V_FLAG_POLICY_CHECK is enabled, allows remote     attackers to cause applications crashes and potentially     allow execution of arbitrary code by triggering failure     of a policy check.

  - CVE-2011-4354     On 32-bit systems, the operations on NIST elliptic     curves P-256 and P-384 are not correctly implemented,     potentially leaking the private ECC key of a TLS server.
    (Regular RSA-based keys are not affected by this     vulnerability.)

  - CVE-2011-4576     The SSL 3.0 implementation does not properly initialize     data structures for block cipher padding, which might     allow remote attackers to obtain sensitive information     by decrypting the padding data sent by an SSL peer.

  - CVE-2011-4619     The Server Gated Cryptography (SGC) implementation in     OpenSSL does not properly handle handshake restarts,     unnecessarily simplifying CPU exhaustion attacks.

ID	Name	Product	Family	Severity
57887	Ubuntu 8.04 LTS / 10.04 LTS / 10.10 / 11.04 / 11.10 : openssl vulnerabilities (USN-1357-1)	Nessus	Ubuntu Local Security Checks	high
57543	Debian DSA-2390-1 : openssl - several vulnerabilities	Nessus	Debian Local Security Checks	high

Detections

Analytics

CVE-2011-4354

high

Tenable Plugins

high

high