How severe is CVE-1999-0821?

CVE-1999-0821 has a CVSS 2.0 base score of 4.6, rated medium severity.

Is CVE-1999-0821 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-0821?

CVE-1999-0821 affects Freebsd. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-1999-0821?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-1999-0821 published?

CVE-1999-0821 was published on 1999-11-08 and last updated on 2026-06-16.

CVE-1999-0821

CVE-1999-0821 is a medium-severity vulnerability in Freebsd with a CVSS 2.0 base score of 4.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 2.0 base score 4.6)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Freebsd
Published: 1999-11-08
Last modified: 2026-06-16

Description

FreeBSD seyon allows local users to gain privileges by providing a malicious program in the -emulator argument.

Frequently asked questions

What is CVE-1999-0821?: FreeBSD seyon allows local users to gain privileges by providing a malicious program in the -emulator argument.
How severe is CVE-1999-0821?: CVE-1999-0821 has a CVSS 2.0 base score of 4.6, rated medium severity.
Is CVE-1999-0821 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-0821?: CVE-1999-0821 affects Freebsd. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-1999-0821?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-1999-0821 published?: CVE-1999-0821 was published on 1999-11-08 and last updated on 2026-06-16.

References

http://www.securityfocus.com/bid/838

Affected products (1)

cpe:2.3:o:freebsd:freebsd:3.3:*:*:*:*:*:*:*

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