Predictable TCP ISN in Packeteer PacketShaper

Credit: nnposter
Risk: Low
Local: Yes
Remote: No
CWE: CWE-Other

CVSS Base Score: 7.5/10
Impact Subscore: 6.4/10
Exploitability Subscore: 10/10
Exploit range: Remote
Attack complexity: Low
Authentication: No required
Confidentiality impact: Partial
Integrity impact: Partial
Availability impact: Partial

Predictable TCP ISN in Packeteer PacketShaper Critical: Less critical Impact: Connection spoofing, DoS Where: Local network Product: Packeteer PacketShaper Description: The TCP/IP stack of Packeteer PacketShaper is generating predictable initial sequence numbers (ISN): The sequence number is incremented by 128000 per second and by 64000 per connection. (As an example, if the current SYN/ACK ISN is 319104000 then about six seconds later the ISN is likely to be 319936000.) This allows an attacker to spoof connections from trusted clients or launch a DoS attack. This type of vulnerability has been described over ten years ago in: * CERT Advisory CA-1995-01 * RFC 1948 The vulnerability has been identified in versions 7.3.0g2 and 7.5.0g1. However, other versions may be also affected. Solution: Restrict network access to the device management interfaces Found by: nnposter

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