CVE-1999-0821FreeBSD seyon allows local users to gain privileges by providing a malicious program in the -emulator argument.
- 4.6MediumCVSS base score
- 0.77%Exploitation in 30 daysEPSS · top 44% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- 2Public exploitsMetasploit, Nuclei and Exploit-DB
Description
FreeBSD seyon allows local users to gain privileges by providing a malicious program in the -emulator argument.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list 2 Exploit-DB entries for it.
Show the exploits2
Exploit-DB2 entries
- Seyon 2.1 rev. 4b i586-Linux (RedHat 4.0/5.1) - Local Overflow (Exploit-DB entry) (opens in a new tab)
EDB-ID 252local, linuxpublished 15 Jan 2001Verified
- FreeBSD 3.3 - Seyon SetGID Dialer (Exploit-DB entry) (opens in a new tab)
EDB-ID 19651local, freebsdpublished 1 Dec 1999Verified
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By mitre
- 59 days later
· 59 days later
Published
- 25 years later
· 25 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
- EPSS (exploitation in 30 days)
- 0.77% · top 44% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.6.
Affected products
n/a
- affected n/a
References
References1
- 838 (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)
- EUVD EUVD-1999-0802 (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://cveledger.app/cve/CVE-1999-0821)Record last updated .