Asterisk Multiple Vulnerabilities (AST-2016-001 - AST-2016-003) (BEAST)

medium Nessus Plugin ID 88715
New! Vulnerability Priority Rating (VPR)

Tenable calculates a dynamic VPR for every vulnerability. VPR combines vulnerability information with threat intelligence and machine learning algorithms to predict which vulnerabilities are most likely to be exploited in attacks. Read more about what VPR is and how it is different from CVSS.

VPR Score: 1.4


A telephony application running on the remote host is affected by multiple vulnerabilities.


According to its SIP banner, the version of Asterisk running on the remote host is affected by the following vulnerabilities :

- An information disclosure vulnerability, known as BEAST, exists in the SSL 3.0 and TLS 1.0 protocols due to a flaw in the way the initialization vector (IV) is selected when operating in cipher-block chaining (CBC) modes. A man-in-the-middle attacker can exploit this to obtain plaintext HTTP header data, by using a blockwise chosen-boundary attack (BCBA) on an HTTPS session, in conjunction with JavaScript code that uses the HTML5 WebSocket API, the Java URLConnection API, or the Silverlight WebClient API. (CVE-2011-3389)

- An integer overflow condition exists in sip.conf due to improper validation of user-supplied input when handling 'timert1' values. A remote attacker can exploit this to cause a denial of service.

- An unspecified flaw exists due to improper handling of FAT data in UDPTL packets. A remote attacker can exploit this to cause a denial of service.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.


Upgrade to Asterisk version 11.21.1 / 13.7.1 / 11.6-cert12 / 13.1-cert3. Alternatively, apply the appropriate patch referenced in the vendor advisories.

See Also

Plugin Details

Severity: Medium

ID: 88715

File Name: asterisk_ast_2016_003.nasl

Version: 1.12

Type: remote

Family: Misc.

Published: 2/12/2016

Updated: 11/19/2019

Configuration: Enable paranoid mode

Risk Information

Risk Factor: Medium

VPR Score: 1.4

CVSS Score Source: CVE-2011-3389

CVSS v2.0

Base Score: 4.3

Temporal Score: 3.2

Vector: AV:N/AC:M/Au:N/C:P/I:N/A:N

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:digium:asterisk

Required KB Items: asterisk/sip_detected, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 2/3/2016

Vulnerability Publication Date: 8/31/2011

Reference Information

CVE: CVE-2011-3389

BID: 49778, 82651, 82656, 82670

CERT: 864643