J-Security Center

Title: Cisco Catalyst Non-Standard TCP Flags Remote Denial Of Service Vulnerability

Severity: HIGH

Description:

Catalyst is a network switch hardware and firmware combination maintained and distributed by Cisco Systems.

A problem with Cisco Catalyst switches has been reported in the handling of non-standard TCP packets. Because of this, an attacker may be able to deny legitimate user access to the switch.

The problem is in the handling of TCP packets which have non-standard TCP flags. Though specific details about this problem are not available, this likely includes a mixed combination of TCP SYN, FIN, ACK, RST, and URG flags that do not commonly occur in networks.

When eight of these packets are received by a specific service on the Catalyst, the service ceases normal operation. To resume normal operation of these services, the switch requires a reboot.

It should be noted that this vulnerability only affects the services operating on the switch, and does not affect the switches availability to handle traffic. This problem affects 4000, 5000, and 6000 series switches.

Affected Products:

  • Cisco CatOS 4.1.0 (1)
  • Cisco CatOS 4.1.0 (2)
  • Cisco CatOS 4.1.0 (3)
  • Cisco CatOS 4.2.0 (1)
  • Cisco CatOS 4.2.0 (2)
  • Cisco CatOS 4.3.0 (1a)
  • Cisco CatOS 4.4.0 (1)
  • Cisco CatOS 4.5.0 (1)
  • Cisco CatOS 4.5.0 (10)
  • Cisco CatOS 4.5.0 (11)
  • Cisco CatOS 4.5.0 (12)
  • Cisco CatOS 4.5.0 (12a)
  • Cisco CatOS 4.5.0 (13)
  • Cisco CatOS 4.5.0 (13a)
  • Cisco CatOS 4.5.0 (2)
  • Cisco CatOS 4.5.0 (3)
  • Cisco CatOS 4.5.0 (4)
  • Cisco CatOS 4.5.0 (5)
  • Cisco CatOS 4.5.0 (6)
  • Cisco CatOS 4.5.0 (6a)
  • Cisco CatOS 4.5.0 (7)
  • Cisco CatOS 4.5.0 (8)
  • Cisco CatOS 4.5.0 (9)
  • Cisco CatOS 5.1.0 (1)
  • Cisco CatOS 5.1.0 (1)CSX
  • Cisco CatOS 5.1.0 (1a)
  • Cisco CatOS 5.1.0 (1a)CSX
  • Cisco CatOS 5.1.0 (2a)
  • Cisco CatOS 5.1.0 (2b)
  • Cisco CatOS 5.2.0 (1)
  • Cisco CatOS 5.2.0 (1)CSX
  • Cisco CatOS 5.2.0 (2)
  • Cisco CatOS 5.2.0 (2)CSX
  • Cisco CatOS 5.2.0 (3)
  • Cisco CatOS 5.2.0 (3)CSX
  • Cisco CatOS 5.2.0 (3a)CSX
  • Cisco CatOS 5.2.0 (4)
  • Cisco CatOS 5.2.0 (5)
  • Cisco CatOS 5.2.0 (6)
  • Cisco CatOS 5.2.0 (7)
  • Cisco CatOS 5.2.0 (7a)
  • Cisco CatOS 5.3.0 (1a)CSX
  • Cisco CatOS 5.3.0 (2)CSX
  • Cisco CatOS 5.3.0 (3)CSX
  • Cisco CatOS 5.3.0 (4)CSX
  • Cisco CatOS 5.3.0 (5)CSX
  • Cisco CatOS 5.3.0 (5a)CSX
  • Cisco CatOS 5.3.0 (6)CSX
  • Cisco CatOS 5.3.0 (6a)CSX
  • Cisco CatOS 5.4.0
  • Cisco CatOS 5.4.0 (1)
  • Cisco CatOS 5.4.0 (2)
  • Cisco CatOS 5.4.0 (2a)
  • Cisco CatOS 5.4.0 (3)
  • Cisco CatOS 5.4.0 (4)
  • Cisco CatOS 5.4.0 (4a)
  • Cisco CatOS 5.5.0
  • Cisco CatOS 5.5.0 (1)
  • Cisco CatOS 5.5.0 (10)
  • Cisco CatOS 5.5.0 (10a)
  • Cisco CatOS 5.5.0 (11)
  • Cisco CatOS 5.5.0 (11a)
  • Cisco CatOS 5.5.0 (12)
  • Cisco CatOS 5.5.0 (12a)
  • Cisco CatOS 5.5.0 (13)
  • Cisco CatOS 5.5.0 (13.5)
  • Cisco CatOS 5.5.0 (13a)
  • Cisco CatOS 5.5.0 (1a)
  • Cisco CatOS 5.5.0 (2)
  • Cisco CatOS 5.5.0 (3)
  • Cisco CatOS 5.5.0 (4)
  • Cisco CatOS 5.5.0 (4a)
  • Cisco CatOS 5.5.0 (4b)
  • Cisco CatOS 5.5.0 (5)
  • Cisco CatOS 5.5.0 (6)
  • Cisco CatOS 5.5.0 (6a)
  • Cisco CatOS 5.5.0 (7)
  • Cisco CatOS 5.5.0 (7a)
  • Cisco CatOS 5.5.0 (8)
  • Cisco CatOS 5.5.0 (8a)
  • Cisco CatOS 5.5.0 (8a)CV
  • Cisco CatOS 5.5.0 (9)
  • Cisco CatOS 6.1.0
  • Cisco CatOS 6.1.0 (1)
  • Cisco CatOS 6.1.0 (1a)
  • Cisco CatOS 6.1.0 (1b)
  • Cisco CatOS 6.1.0 (1c)
  • Cisco CatOS 6.1.0 (1d)
  • Cisco CatOS 6.1.0 (1e)
  • Cisco CatOS 6.1.0 (2)
  • Cisco CatOS 6.1.0 (2a)
  • Cisco CatOS 6.1.0 (3)
  • Cisco CatOS 6.1.0 (3a)
  • Cisco CatOS 6.1.0 (4)
  • Cisco CatOS 6.1.0 (4b)
  • Cisco CatOS 6.2.0 (1)
  • Cisco CatOS 6.2.0 (1a)
  • Cisco CatOS 6.2.0 (2)
  • Cisco CatOS 6.2.0 (2a)
  • Cisco CatOS 6.2.0 (3)
  • Cisco CatOS 6.2.0 (3a)
  • Cisco CatOS 6.3.0 (1)
  • Cisco CatOS 6.3.0 (2)
  • Cisco CatOS 6.3.0 (2a)
  • Cisco CatOS 6.3.0 (3)
  • Cisco CatOS 6.3.0 (3)x
  • Cisco CatOS 6.3.0 (3)x1
  • Cisco CatOS 6.3.0 (3a)
  • Cisco CatOS 6.3.0 (4)
  • Cisco CatOS 6.3.0 (4a)
  • Cisco CatOS 6.3.0 (5)
  • Cisco CatOS 6.3.0 (5.10)
  • Cisco CatOS 7.1.0 (1)
  • Cisco CatOS 7.1.0 (2)
  • Cisco CatOS 7.1.0 (2a)
  • Cisco CatOS 7.1.0(1a)
  • Cisco CatOS 7.4.0
  • Cisco Catalyst 5000 5.5.0(13)

References:

Juniper Networks provides this content via a wide variety of sources and production methods. If notified of errors or omissions in the content of this page, Juniper Networks, at its discretion, will modify or remove the page or leave the content as is, depending on various factors including but not limited to the reputation and authority of the party providing the notification. Please use the contact information displayed elsewhere on this page to report any errors or omissions regarding the content on this page.