CVE-1999-0393

NONECVSS 0.0Weaponized

0.0

Remote attackers can cause a denial of service in Sendmail 8.8.x and 8.9.2 by sending messages with a large number of headers.

CVSS v3: —
EG Score: —
EPSS: 90.9%
KEV: Not listed

Published

January 1, 1999

Last Modified

April 16, 2026

References (2)

cve@mitrehttp://marc.info/?l=bugtraq&m=91694391227372&w=2
af854a3a-2127-422b-91ae-364da2661108http://marc.info/?l=bugtraq&m=91694391227372&w=2

Data Freshness Timeline

(refreshed 11× in last 7d / 17× 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.

2026-05-29 13:40 UTCepss_batch
2026-05-28 13:42 UTCepss_batch
2026-05-28 13:42 UTCepss_batch
2026-05-28 13:42 UTCepss_batch
2026-05-28 13:42 UTCepss_batch
2026-05-27 13:37 UTCepss_batch
2026-05-27 13:37 UTCepss_batch
2026-05-26 13:41 UTCepss_batch
2026-05-26 13:41 UTCepss_batch
2026-05-26 13:41 UTCepss_batch
2026-05-24 16:42 UTCepss_batch
2026-05-21 22:38 UTCepss_batch
2026-05-20 22:36 UTCepss_batch
2026-05-20 11:20 UTCepss_batch
2026-05-20 11:20 UTCepss_batch
2026-05-18 21:29 UTCepss_batch
2026-05-18 21:29 UTCepss_batch

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

Exploit-DBEDB-23167✓ verified
First seen Dec 12, 1998
Sendmail 8.9.2 - Headers Prescan Denial of Service
Open source ↗

Frequently asked(4)

What is CVE-1999-0393?

CVE-1999-0393 is a none vulnerability published on January 1, 1999. Remote attackers can cause a denial of service in Sendmail 8.8.x and 8.9.2 by sending messages with a large number of headers.

When was CVE-1999-0393 disclosed?

CVE-1999-0393 was first published in the National Vulnerability Database on January 1, 1999, 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-1999-0393 actively exploited?

CVE-1999-0393 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 90.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

How do I remediate CVE-1999-0393?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-1999-0393, 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.

Dependency Blast Radius

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CVE-1999-0393

📅 Published

🔄 Last Modified

🔗 References (2)