{"cve":"CVE-2005-0066","nvd":{"published":"2004-12-22T05:00:00.000","modified":"2026-06-16T22:10:26.530","status":"Modified","description":"The original design of TCP does not check that the TCP Acknowledgement number in an ICMP error message generated by an intermediate router is within the range of possible values for data that has already been acknowledged (aka \"TCP acknowledgement number checking\"), which makes it easier for attackers to forge ICMP error messages for specific TCP connections and cause a denial of service, as demonstrated using (1) blind connection-reset attacks with forged \"Destination Unreachable\" messages, (2) blind throughput-reduction attacks with forged \"Source Quench\" messages, or (3) blind throughput-reduction attacks with forged ICMP messages that cause the Path MTU to be reduced.  NOTE: CVE-2004-0790, CVE-2004-0791, and CVE-2004-1060 have been SPLIT based on different attacks; CVE-2005-0065, CVE-2005-0066, CVE-2005-0067, and CVE-2005-0068 are related identifiers that are SPLIT based on the underlying vulnerability.  While CVE normally SPLITs based on vulnerability, the attack-based identifiers exist due to the variety and number of affected implementations and solutions that address the attacks instead of the underlying vulnerabilities.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html","http://www.securityfocus.com/bid/13124","http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html","http://www.securityfocus.com/bid/13124"],"products":["tcp:tcp"],"source":"nvd","synced_at":"2026-10-19T19:37:11.487553034+00:00"},"epss":{"cve":"CVE-2005-0066","score":0.10742,"percentile":0.95826,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}