Cisco CatOS 5.x before 5.5(20) through 8.x before 8.2(2) and 8.3(2)GLX, as used in Catalyst switches, allows remote attackers to cause a denial of service (system crash and reload) by sending invalid packets instead of the final ACK portion of the three-way handshake to the (1) Telnet, (2) HTTP, or (3) SSH services, aka "TCP-ACK DoS attack."
CVE-2004-0551 is a security vulnerability that . Impacting 24 products from cisco, from cisco, from cisco and 21 others, organizations running these solutions should prioritize assessment and patching.
Originally identified in 2004, this vulnerability predates many modern security frameworks and practices. The vulnerability landscape of that era was characterized by different threat models and less mature defense mechanisms compared to contemporary standards.
2004-08-06T04:00:00.000
2025-04-03T01:03:51.193
Deferred
CVSSv2: 5.0 (MEDIUM)
AV:N/AC:L/Au:N/C:N/I:N/A:P
10.0
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | cisco | catos | 2.1\(1\) | Yes |
| Operating System | cisco | catos | 2.1\(2\) | Yes |
| Operating System | cisco | catos | 2.1\(3\) | Yes |
| Operating System | cisco | catos | 2.1\(4\) | Yes |
| Operating System | cisco | catos | 2.1\(5\) | Yes |
| Operating System | cisco | catos | 2.1\(6\) | Yes |
| Operating System | cisco | catos | 2.1\(7\) | Yes |
| Operating System | cisco | catos | 2.1\(8\) | Yes |
| Operating System | cisco | catos | 2.1\(9\) | Yes |
| Operating System | cisco | catos | 2.1\(10\) | Yes |
| Operating System | cisco | catos | 2.1\(11\) | Yes |
| Operating System | cisco | catos | 2.1\(12\) | Yes |
| Operating System | cisco | catos | 2.2\(1\) | Yes |
| Operating System | cisco | catos | 2.2\(2\) | Yes |
| Operating System | cisco | catos | 2.3\(1\) | Yes |
| Operating System | cisco | catos | 2.4\(1\) | Yes |
| Operating System | cisco | catos | 2.4\(2\) | Yes |
| Operating System | cisco | catos | 2.4\(3\) | Yes |
| Operating System | cisco | catos | 2.4\(4\) | Yes |
| Operating System | cisco | catos | 2.4\(5\) | Yes |
| Operating System | cisco | catos | 2.4\(5a\) | Yes |
| Operating System | cisco | catos | 3.0\(7\) | Yes |
| Operating System | cisco | catos | 3.1\(1\) | Yes |
| Operating System | cisco | catos | 3.1\(2\) | Yes |
| Operating System | cisco | catos | 3.1\(2a\) | Yes |
| Operating System | cisco | catos | 3.2\(1\) | Yes |
| Operating System | cisco | catos | 3.2\(1b\) | Yes |
| Operating System | cisco | catos | 3.2\(2\) | Yes |
| Operating System | cisco | catos | 3.2\(3\) | Yes |
| Operating System | cisco | catos | 3.2\(4\) | Yes |
| Operating System | cisco | catos | 3.2\(5\) | Yes |
| Operating System | cisco | catos | 3.2\(6\) | Yes |
| Operating System | cisco | catos | 3.2\(7\) | Yes |
| Operating System | cisco | catos | 3.2\(8\)gdr | Yes |
| Operating System | cisco | catos | 4.1\(1\) | Yes |
| Operating System | cisco | catos | 4.1\(2\) | Yes |
| Operating System | cisco | catos | 4.1\(3\) | Yes |
| Operating System | cisco | catos | 4.2\(1\) | Yes |
| Operating System | cisco | catos | 4.2\(2\) | Yes |
| Operating System | cisco | catos | 4.3\(1a\) | Yes |
| Operating System | cisco | catos | 4.4\(1\) | Yes |
| Operating System | cisco | catos | 4.5\(1\) | Yes |
| Operating System | cisco | catos | 4.5\(2\) | Yes |
| Operating System | cisco | catos | 4.5\(3\) | Yes |
| Operating System | cisco | catos | 4.5\(4\) | Yes |
| Operating System | cisco | catos | 4.5\(5\) | Yes |
| Operating System | cisco | catos | 4.5\(6\) | Yes |
| Operating System | cisco | catos | 4.5\(6a\) | Yes |
| Operating System | cisco | catos | 4.5\(7\) | Yes |
| Operating System | cisco | catos | 4.5\(8\) | Yes |
| Operating System | cisco | catos | 4.5\(9\) | Yes |
| Operating System | cisco | catos | 4.5\(10\) | Yes |
| Operating System | cisco | catos | 4.5\(11\) | Yes |
| Operating System | cisco | catos | 4.5\(12\) | Yes |
| Operating System | cisco | catos | 4.5\(12a\) | Yes |
| Operating System | cisco | catos | 4.5\(13\) | Yes |
| Operating System | cisco | catos | 4.5\(13a\) | Yes |
| Operating System | cisco | catos | 4.5\(14\) | Yes |
| Operating System | cisco | catos | 5.1\(1\) | Yes |
| Operating System | cisco | catos | 5.1\(1\)csx | Yes |
| Operating System | cisco | catos | 5.1\(1a\) | Yes |
| Operating System | cisco | catos | 5.1\(1a\)csx | Yes |
| Operating System | cisco | catos | 5.1\(2a\) | Yes |
| Operating System | cisco | catos | 5.1\(2b\) | Yes |
| Operating System | cisco | catos | 5.2\(1\) | Yes |
| Operating System | cisco | catos | 5.2\(1\)csx | Yes |
| Operating System | cisco | catos | 5.2\(2\) | Yes |
| Operating System | cisco | catos | 5.2\(2\)csx | Yes |
| Operating System | cisco | catos | 5.2\(3\) | Yes |
| Operating System | cisco | catos | 5.2\(3\)csx | Yes |
| Operating System | cisco | catos | 5.2\(3a\)csx | Yes |
| Operating System | cisco | catos | 5.2\(4\) | Yes |
| Operating System | cisco | catos | 5.2\(5\) | Yes |
| Operating System | cisco | catos | 5.2\(6\) | Yes |
| Operating System | cisco | catos | 5.2\(7\) | Yes |
| Operating System | cisco | catos | 5.2\(7a\) | Yes |
| Operating System | cisco | catos | 5.3\(1a\)csx | Yes |
| Operating System | cisco | catos | 5.3\(2\)csx | Yes |
| Operating System | cisco | catos | 5.3\(3\)csx | Yes |
| Operating System | cisco | catos | 5.3\(4\)csx | Yes |
| Operating System | cisco | catos | 5.3\(5\)csx | Yes |
| Operating System | cisco | catos | 5.3\(5a\)csx | Yes |
| Operating System | cisco | catos | 5.3\(6\)csx | Yes |
| Operating System | cisco | catos | 5.3\(6a\)csx | Yes |
| Operating System | cisco | catos | 5.4 | Yes |
| Operating System | cisco | catos | 5.4\(1\) | Yes |
| Operating System | cisco | catos | 5.4\(1\)deferred | Yes |
| Operating System | cisco | catos | 5.4\(2\) | Yes |
| Operating System | cisco | catos | 5.4\(2a\) | Yes |
| Operating System | cisco | catos | 5.4\(3\) | Yes |
| Operating System | cisco | catos | 5.4\(4\) | Yes |
| Operating System | cisco | catos | 5.4\(4a\) | Yes |
| Operating System | cisco | catos | 5.5 | Yes |
| Operating System | cisco | catos | 5.5\(1\) | Yes |
| Operating System | cisco | catos | 5.5\(1a\) | Yes |
| Operating System | cisco | catos | 5.5\(2\) | Yes |
| Operating System | cisco | catos | 5.5\(3\) | Yes |
| Operating System | cisco | catos | 5.5\(4\) | Yes |
| Operating System | cisco | catos | 5.5\(4a\) | Yes |
| Operating System | cisco | catos | 5.5\(4b\) | Yes |
| Operating System | cisco | catos | 5.5\(5\) | Yes |
| Operating System | cisco | catos | 5.5\(6\) | Yes |
| Operating System | cisco | catos | 5.5\(6a\) | Yes |
| Operating System | cisco | catos | 5.5\(7\) | Yes |
| Operating System | cisco | catos | 5.5\(7a\) | Yes |
| Operating System | cisco | catos | 5.5\(8\) | Yes |
| Operating System | cisco | catos | 5.5\(8a\) | Yes |
| Operating System | cisco | catos | 5.5\(8a\)cv | Yes |
| Operating System | cisco | catos | 5.5\(9\) | Yes |
| Operating System | cisco | catos | 5.5\(10\) | Yes |
| Operating System | cisco | catos | 5.5\(10a\) | Yes |
| Operating System | cisco | catos | 5.5\(11\) | Yes |
| Operating System | cisco | catos | 5.5\(11a\) | Yes |
| Operating System | cisco | catos | 5.5\(12\) | Yes |
| Operating System | cisco | catos | 5.5\(12a\) | Yes |
| Operating System | cisco | catos | 5.5\(13\) | Yes |
| Operating System | cisco | catos | 5.5\(13.5\) | Yes |
| Operating System | cisco | catos | 5.5\(13a\) | Yes |
| Operating System | cisco | catos | 5.5\(14\) | Yes |
| Operating System | cisco | catos | 5.5\(15\) | Yes |
| Operating System | cisco | catos | 5.5\(16\) | Yes |
| Operating System | cisco | catos | 5.5\(16.2\) | Yes |
| Operating System | cisco | catos | 5.5\(17\) | Yes |
| Operating System | cisco | catos | 5.5\(18\) | Yes |
| Operating System | cisco | catos | 5.5\(19\) | Yes |
| Operating System | cisco | catos | 6.1 | Yes |
| Operating System | cisco | catos | 6.1\(1\) | Yes |
| Operating System | cisco | catos | 6.1\(1a\) | Yes |
| Operating System | cisco | catos | 6.1\(1b\) | Yes |
| Operating System | cisco | catos | 6.1\(1c\) | Yes |
| Operating System | cisco | catos | 6.1\(1d\) | Yes |
| Operating System | cisco | catos | 6.1\(1e\) | Yes |
| Operating System | cisco | catos | 6.1\(2\) | Yes |
| Operating System | cisco | catos | 6.1\(2a\) | Yes |
| Operating System | cisco | catos | 6.1\(3\) | Yes |
| Operating System | cisco | catos | 6.1\(3a\) | Yes |
| Operating System | cisco | catos | 6.1\(4\) | Yes |
| Operating System | cisco | catos | 6.1\(4b\) | Yes |
| Operating System | cisco | catos | 6.2\(1\) | Yes |
| Operating System | cisco | catos | 6.2\(1a\) | Yes |
| Operating System | cisco | catos | 6.2\(2\) | Yes |
| Operating System | cisco | catos | 6.2\(2a\) | Yes |
| Operating System | cisco | catos | 6.2\(3\) | Yes |
| Operating System | cisco | catos | 6.2\(3a\) | Yes |
| Operating System | cisco | catos | 6.3\(1\) | Yes |
| Operating System | cisco | catos | 6.3\(1a\) | Yes |
| Operating System | cisco | catos | 6.3\(2\) | Yes |
| Operating System | cisco | catos | 6.3\(2a\) | Yes |
| Operating System | cisco | catos | 6.3\(3\) | Yes |
| Operating System | cisco | catos | 6.3\(3\)x | Yes |
| Operating System | cisco | catos | 6.3\(3\)x1 | Yes |
| Operating System | cisco | catos | 6.3\(3a\) | Yes |
| Operating System | cisco | catos | 6.3\(4\) | Yes |
| Operating System | cisco | catos | 6.3\(4a\) | Yes |
| Operating System | cisco | catos | 6.3\(5\) | Yes |
| Operating System | cisco | catos | 6.3\(5.10\) | Yes |
| Operating System | cisco | catos | 6.3\(6\) | Yes |
| Operating System | cisco | catos | 6.3\(7\) | Yes |
| Operating System | cisco | catos | 6.3\(8\) | Yes |
| Operating System | cisco | catos | 6.3\(8.3\) | Yes |
| Operating System | cisco | catos | 6.3\(9\) | Yes |
| Operating System | cisco | catos | 6.3\(10\) | Yes |
| Operating System | cisco | catos | 6.4\(1\) | Yes |
| Operating System | cisco | catos | 6.4\(2\) | Yes |
| Operating System | cisco | catos | 6.4\(3\) | Yes |
| Operating System | cisco | catos | 6.4\(4a\) | Yes |
| Operating System | cisco | catos | 6.4\(5\) | Yes |
| Operating System | cisco | catos | 6.4\(6\) | Yes |
| Operating System | cisco | catos | 6.4\(7\) | Yes |
| Operating System | cisco | catos | 6.4\(8\) | Yes |
| Operating System | cisco | catos | 7.1\(1\) | Yes |
| Operating System | cisco | catos | 7.1\(1a\) | Yes |
| Operating System | cisco | catos | 7.1\(2\) | Yes |
| Operating System | cisco | catos | 7.1\(2a\) | Yes |
| Operating System | cisco | catos | 7.2\(0.65\) | Yes |
| Operating System | cisco | catos | 7.2\(1\) | Yes |
| Operating System | cisco | catos | 7.2\(2\) | Yes |
| Operating System | cisco | catos | 7.3 | Yes |
| Operating System | cisco | catos | 7.3\(1\) | Yes |
| Operating System | cisco | catos | 7.3\(2\) | Yes |
| Operating System | cisco | catos | 7.4 | Yes |
| Operating System | cisco | catos | 7.4\(0.2\)clr | Yes |
| Operating System | cisco | catos | 7.4\(0.63\) | Yes |
| Operating System | cisco | catos | 7.4\(1\) | Yes |
| Operating System | cisco | catos | 7.4\(2\) | Yes |
| Operating System | cisco | catos | 7.4\(3\) | Yes |
| Operating System | cisco | catos | 7.5 | Yes |
| Operating System | cisco | catos | 7.5\(1\) | Yes |
| Operating System | cisco | catos | 7.6 | Yes |
| Operating System | cisco | catos | 7.6\(1\) | Yes |
| Operating System | cisco | catos | 7.6\(2\) | Yes |
| Operating System | cisco | catos | 7.6\(3\) | Yes |
| Operating System | cisco | catos | 7.6\(4\) | Yes |
| Operating System | cisco | catos | 7.6\(5\) | Yes |
| Operating System | cisco | catos | 8.1 | Yes |
| Operating System | cisco | catos | 8.1\(2\) | Yes |
| Operating System | cisco | catos | 8.1\(3\) | Yes |
| Operating System | cisco | catos | 8.2 | Yes |
| Operating System | cisco | catos | 8.2\(1\) | Yes |
| Operating System | cisco | catos | 8.3\(1\)glx | Yes |
| Operating System | cisco | catos | 8.3glx | Yes |
| Hardware | cisco | catalyst_2901 | * | Yes |
| Hardware | cisco | catalyst_2902 | * | Yes |
| Hardware | cisco | catalyst_2926 | * | Yes |
| Hardware | cisco | catalyst_2926f | * | Yes |
| Hardware | cisco | catalyst_2926gl | * | Yes |
| Hardware | cisco | catalyst_2926gs | * | Yes |
| Hardware | cisco | catalyst_2926t | * | Yes |
| Hardware | cisco | catalyst_2948 | * | Yes |
| Hardware | cisco | catalyst_2948-ge-tx | * | Yes |
| Hardware | cisco | catalyst_2948g-l3 | * | Yes |
| Hardware | cisco | catalyst_2980g | * | Yes |
| Hardware | cisco | catalyst_2980g-a | * | Yes |
| Hardware | cisco | catalyst_4000 | * | Yes |
| Hardware | cisco | catalyst_4500 | * | Yes |
| Hardware | cisco | catalyst_4503 | * | Yes |
| Hardware | cisco | catalyst_4506 | * | Yes |
| Hardware | cisco | catalyst_4507r | * | Yes |
| Hardware | cisco | catalyst_4510r | * | Yes |
| Hardware | cisco | catalyst_4912g | * | Yes |
| Hardware | cisco | catalyst_5000 | * | Yes |
| Hardware | cisco | catalyst_6000_ws-svc-nam-1 | 2.2\(1a\) | Yes |
| Hardware | cisco | catalyst_6000_ws-svc-nam-1 | 3.1\(1a\) | Yes |
| Hardware | cisco | catalyst_6000_ws-svc-nam-2 | 2.2\(1a\) | Yes |
| Hardware | cisco | catalyst_6000_ws-svc-nam-2 | 3.1\(1a\) | Yes |
| Hardware | cisco | catalyst_6000_ws-x6380-nam | 2.1\(2\) | Yes |
| Hardware | cisco | catalyst_6000_ws-x6380-nam | 3.1\(1a\) | Yes |
| Operating System | cisco | catos | 4.5\(2\) | Yes |
| Operating System | cisco | catos | 4.5\(3\) | Yes |
| Operating System | cisco | catos | 4.5\(4\) | Yes |
| Operating System | cisco | catos | 4.5\(4b\) | Yes |
| Operating System | cisco | catos | 4.5\(5\) | Yes |
| Operating System | cisco | catos | 4.5\(6\) | Yes |
| Operating System | cisco | catos | 4.5\(7\) | Yes |
| Operating System | cisco | catos | 4.5\(8\) | Yes |
| Operating System | cisco | catos | 4.5\(9\) | Yes |
| Operating System | cisco | catos | 4.5\(10\) | Yes |
| Operating System | cisco | catos | 4.5\(11\) | Yes |
| Operating System | cisco | catos | 4.5\(12\) | Yes |
| Operating System | cisco | catos | 4.5\(13a\) | Yes |
| Operating System | cisco | catos | 4.5.10 | Yes |
| Operating System | cisco | catos | 5.1 | Yes |
| Operating System | cisco | catos | 5.1\(1\) | Yes |
| Operating System | cisco | catos | 5.1\(1a\) | Yes |
| Operating System | cisco | catos | 5.1\(2a\) | Yes |
| Operating System | cisco | catos | 5.2 | Yes |
| Operating System | cisco | catos | 5.2\(1\) | Yes |
| Operating System | cisco | catos | 5.2\(1a\) | Yes |
| Operating System | cisco | catos | 5.2\(2\) | Yes |
| Operating System | cisco | catos | 5.2\(3\) | Yes |
| Operating System | cisco | catos | 5.2\(4\) | Yes |
| Operating System | cisco | catos | 5.2\(5\) | Yes |
| Operating System | cisco | catos | 5.2\(6\) | Yes |
| Operating System | cisco | catos | 5.2\(7\) | Yes |
| Operating System | cisco | catos | 5.3\(1\)csx | Yes |
| Operating System | cisco | catos | 5.3\(1a\)csx | Yes |
| Operating System | cisco | catos | 5.3\(2\)csx | Yes |
| Operating System | cisco | catos | 5.3\(3\)csx | Yes |
| Operating System | cisco | catos | 5.3\(4\)csx | Yes |
| Operating System | cisco | catos | 5.3\(5\)csx | Yes |
| Operating System | cisco | catos | 5.3\(5a\)csx | Yes |
| Operating System | cisco | catos | 5.3\(6\)csx | Yes |
| Operating System | cisco | catos | 5.4 | Yes |
| Operating System | cisco | catos | 5.4\(1\) | Yes |
| Operating System | cisco | catos | 5.4\(2\) | Yes |
| Operating System | cisco | catos | 5.4\(3\) | Yes |
| Operating System | cisco | catos | 5.4\(4\) | Yes |
| Operating System | cisco | catos | 5.5 | Yes |
| Operating System | cisco | catos | 5.5\(1\) | Yes |
| Operating System | cisco | catos | 5.5\(2\) | Yes |
| Operating System | cisco | catos | 5.5\(3\) | Yes |
| Operating System | cisco | catos | 5.5\(4\) | Yes |
| Operating System | cisco | catos | 5.5\(4a\) | Yes |
| Operating System | cisco | catos | 5.5\(4b\) | Yes |
| Operating System | cisco | catos | 5.5\(5\) | Yes |
| Operating System | cisco | catos | 5.5\(6\) | Yes |
| Operating System | cisco | catos | 5.5\(7\) | Yes |
| Operating System | cisco | catos | 5.5\(13\) | Yes |
| Operating System | cisco | catos | 6.1\(1\) | Yes |
| Operating System | cisco | catos | 6.1\(1a\) | Yes |
| Operating System | cisco | catos | 6.1\(1b\) | Yes |
| Operating System | cisco | catos | 6.1\(1c\) | Yes |
| Operating System | cisco | catos | 6.1\(2\) | Yes |
| Operating System | cisco | catos | 6.1\(2.13\) | Yes |
| Operating System | cisco | catos | 6.1\(3\) | Yes |
| Operating System | cisco | catos | 6.2\(0.110\) | Yes |
| Operating System | cisco | catos | 6.2\(0.111\) | Yes |
| Operating System | cisco | catos | 6.3\(0.7\)pan | Yes |
| Operating System | cisco | catos | 6.3\(4\) | Yes |
| Operating System | cisco | catos | 6.3\(5\) | Yes |
| Operating System | cisco | catos | 7.1 | Yes |
| Operating System | cisco | catos | 7.1\(2\) | Yes |
| Operating System | cisco | catos | 7.5\(1\) | Yes |
| Operating System | cisco | catos | 7.6\(1\) | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cisco's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.