OpenSSL 1.0.1 < 1.0.1s / 1.0.2 < 1.0.2g Multiple Vulnerabilities (DROWN)

medium Log Correlation Engine Plugin ID 801963
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Synopsis

The remote web server is running an outdated instance of OpenSSL and thus may be missing patches for multiple vulnerabilities.

Description

Versions of OpenSSL prior to 1.0.1s, or 1.0.2g are unpatched for the following vulnerabilities :

According to its banner, the remote host is running a version of OpenSSL 1.0.2 prior to 1.0.2g. It is, therefore, affected by the following vulnerabilities :

- A key disclosure vulnerability exists due to improper handling of cache-bank conflicts on the Intel Sandy-bridge microarchitecture. An attacker can exploit this to gain access to RSA key information. (CVE-2016-0702)

- A double-free error exists due to improper validation of user-supplied input when parsing malformed DSA private keys. A remote attacker can exploit this to corrupt memory, resulting in a denial of service condition or the execution of arbitrary code. (CVE-2016-0705)

- A NULL pointer dereference flaw exists in the BN_hex2bn() and BN_dec2bn() functions. A remote attacker can exploit this to trigger a heap corruption, resulting in the execution of arbitrary code. (CVE-2016-0797)

- A denial of service vulnerability exists due to improper handling of invalid usernames. A remote attacker can exploit this, via a specially crafted username, to leak 300 bytes of memory per connection, exhausting available memory resources. (CVE-2016-0798)

- Multiple memory corruption issues exist that allow a remote attacker to cause a denial of service condition or the execution of arbitrary code. (CVE-2016-0799)

- A flaw exists that allows a cross-protocol Bleichenbacher padding oracle attack known as DROWN (Decrypting RSA with Obsolete and Weakened eNcryption). This vulnerability exists due to a flaw in the Secure Sockets Layer Version 2 (SSLv2) implementation, and it allows captured TLS traffic to be decrypted. A man-in-the-middle attacker can exploit this to decrypt the TSL connection by utilizing previously captured traffic and weak cryptography along with a series of specially crafted connections to an SSLv2 server that uses the same private key. (CVE-2016-0800)

Solution

OpenSSL versions 1.0.1s and 1.0.2g are patched against these vulnerabilities. Apply the vendors patch, or update to these versions or later.

See Also

https://drownattack.com/

https://www.openssl.org/news/secadv/20160301.txt

https://www.openssl.org/news/cl101.txt

https://drownattack.com/drown-attack-paper.pdf

Plugin Details

Severity: Medium

ID: 801963

Family: Web Servers

Published: 3/7/2016

Updated: 3/7/2016

Nessus ID: 89081, 89082

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 4

Temporal Score: 3.3

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N

Temporal Vector: CVSS2#E:F/RL:OF/RC:C

Vulnerability Information

Patch Publication Date: 3/1/2016

Vulnerability Publication Date: 3/1/2016

Reference Information

CVE: CVE-2016-0705, CVE-2016-0702, CVE-2016-0797, CVE-2016-0798, CVE-2016-0799, CVE-2016-0800