SSL / TLS Renegotiation Handshakes MiTM Plaintext Data Injection

medium Nessus Plugin ID 42880
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The remote service allows insecure renegotiation of TLS / SSL connections.


The remote service encrypts traffic using TLS / SSL but allows a client to insecurely renegotiate the connection after the initial handshake.
An unauthenticated, remote attacker may be able to leverage this issue to inject an arbitrary amount of plaintext into the beginning of the application protocol stream, which could facilitate man-in-the-middle attacks if the service assumes that the sessions before and after renegotiation are from the same 'client' and merges them at the application layer.


Contact the vendor for specific patch information.

See Also

Plugin Details

Severity: Medium

ID: 42880

File Name: ssl_renegotiation.nasl

Version: 1.48

Type: remote

Family: General

Published: 11/24/2009

Updated: 6/12/2020

Dependencies: ssl_supported_versions.nasl

Risk Information


Risk Factor: Low

Score: 3.3


Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.5

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

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

Vulnerability Information

Required KB Items: SSL/Supported

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 11/5/2009

Vulnerability Publication Date: 11/4/2009

Reference Information

CVE: CVE-2009-3555

BID: 36935

CERT: 120541

CWE: 310