CVE-1999-0284

NONECVSS 0.0Weaponized

0.0

Denial of service to NT mail servers including Ipswitch, Mdaemon, and Exchange through a buffer overflow in the SMTP HELO command.

CVSS v3: —
EG Score: —
EPSS: 87.6%
KEV: Not listed

Published

January 1, 1998

Last Modified

April 16, 2026

References (2)

cve@mitrehttps://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0284
af854a3a-2127-422b-91ae-364da2661108https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0284

Data Freshness Timeline

(refreshed 13× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

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Publicly available exploits

(3 references)

Working exploit code is in the public domain (3 Exploit-DB entries). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

Exploit-DBEDB-23146✓ verified
First seen Mar 10, 1999
Alt-N MDaemon Server 2.71 SP1 - SMTP HELO Argument Buffer Overflow
Open source ↗
Exploit-DBEDB-23145✓ verified
First seen Mar 10, 1998
Ipswitch Imail Server 5.0 - SMTP HELO Argument Buffer Overflow
Open source ↗
Exploit-DBEDB-23113✓ verified
First seen Mar 10, 1998
Microsoft Exchange Server 4.0/5.0 - SMTP HELO Argument Buffer Overflow
Open source ↗

Frequently asked(4)

What is CVE-1999-0284?

CVE-1999-0284 is a none vulnerability published on January 1, 1998. Denial of service to NT mail servers including Ipswitch, Mdaemon, and Exchange through a buffer overflow in the SMTP HELO command.

When was CVE-1999-0284 disclosed?

CVE-1999-0284 was first published in the National Vulnerability Database on January 1, 1998, with the most recent update on April 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-1999-0284 actively exploited?

CVE-1999-0284 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 87.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

How do I remediate CVE-1999-0284?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-1999-0284, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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CVE-1999-0284

📅 Published

🔄 Last Modified

🔗 References (2)