SSL / TLS Renegotiation DoS

medium Nessus Plugin ID 53491
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Synopsis

The remote service allows repeated renegotiation of TLS / SSL connections.

Description

The remote service encrypts traffic using TLS / SSL and permits clients to renegotiate connections. The computational requirements for renegotiating a connection are asymmetrical between the client and the server, with the server performing several times more work. Since the remote host does not appear to limit the number of renegotiations for a single TLS / SSL connection, this permits a client to open several simultaneous connections and repeatedly renegotiate them, possibly leading to a denial of service condition.

Solution

Contact the vendor for specific patch information.

See Also

http://www.ietf.org/mail-archive/web/tls/current/msg07553.html

Plugin Details

Severity: Medium

ID: 53491

File Name: ssl_renegotiation_dos.nasl

Version: 1.17

Type: remote

Family: General

Published: 5/4/2011

Updated: 10/18/2013

Dependencies: ssl_supported_versions.nasl

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.9

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

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

Vulnerability Information

Required KB Items: SSL/Supported

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 3/13/2011

Reference Information

CVE: CVE-2011-1473

BID: 48626

OSVDB: 73894