Vulnerabilities > CVE-2015-5361 - Inadequate Encryption Strength vulnerability in Juniper products

047910
CVSS 5.8 - MEDIUM
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
NONE
network
juniper
CWE-326
nessus

Summary

Background For regular, unencrypted FTP traffic, the FTP ALG can inspect the unencrypted control channel and open related sessions for the FTP data channel. These related sessions (gates) are specific to source and destination IPs and ports of client and server. The design intent of the ftps-extensions option (which is disabled by default) is to provide similar functionality when the SRX secures the FTP/FTPS client. As the control channel is encrypted, the FTP ALG cannot inspect the port specific information and will open a wider TCP data channel (gate) from client IP to server IP on all destination TCP ports. In FTP/FTPS client environments to an enterprise network or the Internet, this is the desired behavior as it allows firewall policy to be written to FTP/FTPS servers on well-known control ports without using a policy with destination IP ANY and destination port ANY. Issue The ftps-extensions option is not intended or recommended where the SRX secures the FTPS server, as the wide data channel session (gate) will allow the FTPS client temporary access to all TCP ports on the FTPS server. The data session is associated to the control channel and will be closed when the control channel session closes. Depending on the configuration of the FTPS server, supporting load-balancer, and SRX inactivity-timeout values, the server/load-balancer and SRX may keep the control channel open for an extended period of time, allowing an FTPS client access for an equal duration.? Note that the ftps-extensions option is not enabled by default.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Brute Force
    In this attack, some asset (information, functionality, identity, etc.) is protected by a finite secret value. The attacker attempts to gain access to this asset by using trial-and-error to exhaustively explore all the possible secret values in the hope of finding the secret (or a value that is functionally equivalent) that will unlock the asset. Examples of secrets can include, but are not limited to, passwords, encryption keys, database lookup keys, and initial values to one-way functions. The key factor in this attack is the attackers' ability to explore the possible secret space rapidly. This, in turn, is a function of the size of the secret space and the computational power the attacker is able to bring to bear on the problem. If the attacker has modest resources and the secret space is large, the challenge facing the attacker is intractable. While the defender cannot control the resources available to an attacker, they can control the size of the secret space. Creating a large secret space involves selecting one's secret from as large a field of equally likely alternative secrets as possible and ensuring that an attacker is unable to reduce the size of this field using available clues or cryptanalysis. Doing this is more difficult than it sounds since elimination of patterns (which, in turn, would provide an attacker clues that would help them reduce the space of potential secrets) is difficult to do using deterministic machines, such as computers. Assuming a finite secret space, a brute force attack will eventually succeed. The defender must rely on making sure that the time and resources necessary to do so will exceed the value of the information. For example, a secret space that will likely take hundreds of years to explore is likely safe from raw-brute force attacks.
  • Encryption Brute Forcing
    An attacker, armed with the cipher text and the encryption algorithm used, performs an exhaustive (brute force) search on the key space to determine the key that decrypts the cipher text to obtain the plaintext.

Nessus

NASL familyJunos Local Security Checks
NASL idJUNIPER_JSA10706.NASL
descriptionAccording to its self-reported version number, the remote Juniper Junos SRX series device is affected by a flaw in handling the ftps-extension option when the SRX secures the FTPS server. An unauthenticated, remote attacker can exploit this flaw to expose TCP ports for arbitrary data channels. Note that this issue only affects devices with the FTP Application Layer Gateway (ALG) enabled with the ftps-extensions option.
last seen2020-03-18
modified2015-10-26
plugin id86607
published2015-10-26
reporterThis script is Copyright (C) 2015-2018 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/86607
titleJuniper Junos SRX Series FTP ALG ftps-extension TCP Port Exposure (JSA10706)

Packetstorm

data sourcehttps://packetstormsecurity.com/files/download/133499/qlikview-xxe.txt
idPACKETSTORM:133499
last seen2016-12-05
published2015-09-09
reporterAlex Haynes
sourcehttps://packetstormsecurity.com/files/133499/Qlikview-11.20-SR4-Blind-XXE-Injection.html
titleQlikview 11.20 SR4 Blind XXE Injection