CVE-2005-0066
The original design of TCP does not check that the TCP Acknowledgement number in an ICMP error message generated by an intermediate router…
- Published
- Updated
- Reserved
- Assigned by
- mitre
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
- EPSS (exploitation in 30 days)
- 10.7% · top 4.2% of all CVEs (4 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.0.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (2)
- 13124 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2005-0066)Record last updated .