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CVE-2002-0518
The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of…
Medium5.0EPSS 2.5%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of service (crash) (1) via a SYN packet that is accepted using syncookies that causes a null pointer to be referenced for the socket's TCP options, or (2) by killing and restarting a process that listens on the same socket, which does not properly clear the old inpcb pointer on restart.
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)
- 2.5% · top 16% of all CVEs (2 Nov 2026)
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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 (4)
- 6046 (opens in a new tab)vdb-entryx_refsource_OSVDBx_transferred
- bsd-syncookie-pointer-dos(8873) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- bsd-syncache-inpcb-dos(8875) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- 4524 (opens in a new tab)vdb-entryx_refsource_BIDx_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)
Record last updated .