{"id":"CVE-2004-0551","aliases":["EUVD-2004-0550","GHSA-cq5p-fgmw-rvxv"],"status":"published","title":"Cisco CatOS 5.x before 5.5(20) through 8.x before 8.2(2) and 8.3(2)GLX, as used in Catalyst...","description":"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.\"","severity":{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.03131,"percentile":0.87959,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"published":"2004-06-15T04:00:00Z","modified":"2026-06-16T22:05:51Z","products":[{"vendor":"cisco","product":"catalyst_2901"},{"vendor":"cisco","product":"catalyst_2902"},{"vendor":"cisco","product":"catalyst_2926"},{"vendor":"cisco","product":"catalyst_2926f"},{"vendor":"cisco","product":"catalyst_2926gl"},{"vendor":"cisco","product":"catalyst_2926gs"},{"vendor":"cisco","product":"catalyst_2926t"},{"vendor":"cisco","product":"catalyst_2948"},{"vendor":"cisco","product":"catalyst_2948-ge-tx"},{"vendor":"cisco","product":"catalyst_2948g-l3"},{"vendor":"cisco","product":"catalyst_2980g"},{"vendor":"cisco","product":"catalyst_2980g-a"},{"vendor":"cisco","product":"catalyst_4000"},{"vendor":"cisco","product":"catalyst_4500"},{"vendor":"cisco","product":"catalyst_4503"},{"vendor":"cisco","product":"catalyst_4506"},{"vendor":"cisco","product":"catalyst_4507r"},{"vendor":"cisco","product":"catalyst_4510r"},{"vendor":"cisco","product":"catalyst_4912g"},{"vendor":"cisco","product":"catalyst_5000"},{"vendor":"cisco","product":"catalyst_6000_ws-svc-nam-1"},{"vendor":"cisco","product":"catalyst_6000_ws-svc-nam-2"},{"vendor":"cisco","product":"catalyst_6000_ws-x6380-nam"},{"vendor":"cisco","product":"catos"}],"references":[{"url":"http://www.kb.cert.org/vuls/id/245190","tags":["third-party-advisory","x_refsource_CERT-VN","x_transferred","Third Party Advisory","US Government Resource"]},{"url":"http://www.cisco.com/warp/public/707/cisco-sa-20040609-catos.shtml","tags":["vendor-advisory","x_refsource_CISCO","x_transferred"]},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/16370","tags":["vdb-entry","x_refsource_XF","x_transferred"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2004-0551"},{"url":"https://github.com/advisories/GHSA-cq5p-fgmw-rvxv"}],"sources":{"cve":[{"id":"CVE-2004-0551","description":"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.\"","status":"published","published":"2004-06-15T04:00:00Z","modified":"2024-08-08T00:24:26.408Z","updated_at":"2026-11-02T14:34:55.098814Z"}],"euvd":[{"id":"EUVD-2004-0550","description":"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.\"","status":"published","published":"2004-06-15T04:00:00Z","modified":"2024-08-08T00:24:26Z","updated_at":"2026-11-03T01:15:18.677356Z"}],"ghsa":[{"id":"GHSA-cq5p-fgmw-rvxv","title":"Cisco CatOS 5.x before 5.5(20) through 8.x before 8.2(2) and 8.3(2)GLX, as used in Catalyst...","description":"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.\"","status":"published","published":"2022-04-29T02:57:56Z","modified":"2023-01-30T05:02:44Z","updated_at":"2026-11-02T14:46:42.642348Z"}],"nvd":[{"id":"CVE-2004-0551","description":"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.\"","status":"published","published":"2004-08-06T04:00:00Z","modified":"2026-06-16T22:05:51.783Z","cvss":[{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:00:51.000028Z"}]}}