CVE-1999-0203

CRITICAL

In Sendmail, attackers can gain root privileges via SMTP by specifying an improper "mail from" address and an invalid "rcpt to" address that would cause the mail to bounce to a program.

Affects 1 product across 1 vendor.

CVSS 2.010.0
EPSS2.1%
Percentile82th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity.
◆ AI Analysis — automated analysis, not human-reviewed

This vulnerability was disclosed in 1995. A critical vulnerability affects Eric Allman systems (CVE-1999-0203). No public exploit code is currently available. Isolate affected systems if patching is not feasible.

BSID: BS-1995-GLOBAL-307682-C • Model: rule-based-v1 • Confidence: MEDIUM

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Frequently Asked Questions
What is CVE-1999-0203?
This vulnerability was disclosed in 1995. A critical vulnerability affects Eric Allman systems (CVE-1999-0203). No public exploit code is currently available. Isolate affected systems if patching is not feasible.
What is the CVSS score for CVE-1999-0203?
CVE-1999-0203 has CVSS 10.0 (Critical). Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C. EPSS: 2.1%.
Is CVE-1999-0203 actively exploited?
No confirmed active exploitation of CVE-1999-0203 as of 2026-06-20.
How do I remediate CVE-1999-0203?
Priority: MEDIUM.
What systems are affected by CVE-1999-0203?
CVE-1999-0203 affects Eric Allman Sendmail.
Vulnerability Details
CVE IDCVE-1999-0203
BSIDBS-1995-GLOBAL-307682-C BreachSpider Global ID
CVSS VectorAV:N/AC:L/Au:N/C:C/I:C/A:C
Published1995-08-17
Last Modified2026-06-16
ICS Relevance0%
SourceNVD
Official Description

In Sendmail, attackers can gain root privileges via SMTP by specifying an improper "mail from" address and an invalid "rcpt to" address that would cause the mail to bounce to a program.

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

Vulnerability details: In Sendmail, attackers can gain root privileges via SMTP by specifying an improper "mail from" address and an invalid "rcpt to" address that would cause the mail to bounce to a program. CVSS vector: AV:N/AC:L/Au:N/C:C/I:C/A:C.

Exploitation Likelihood: LOW

Affected Products
VendorProductAffected Versions
Eric Allman Sendmail 8.6.10
Remediation

No official vendor advisory link on record. See the CVE record →

Threat Intelligence
● Threat Intelligence Validated: October 2026 | Threat Age: 11391 Days
CISA known-exploitedNot in KEV catalog
Public ExploitNot confirmed
PoC CodeNot confirmed
AI Enrichment Record — provenance & audit hash
Modelrule-based-v1
ConfidenceMEDIUM
Enriched At2026-05-24
SHA-512 Audit Hashfebc37db6ce3bbd2693076fd0193776ac44bcbcad6c0d32eae101a40c8b88236da255d111d8991f0852e9a42f3d2d5613c6339e458d9b14456512aae6b8ff27c
Related CVEs affecting Eric Allman
CVE-1999-0204 10.0 Sendmail 8.6.9 allows remote attackers to execute root commands, using ident. CVE-1999-0047 10.0 MIME conversion buffer overflow in sendmail versions 8.8.3 and 8.8.4. CVE-1999-0206 10.0 MIME buffer overflow in Sendmail 8.8.0 and 8.8.1 gives root access. CVE-1999-0095 10.0 The debug command in Sendmail is enabled, allowing attackers to execute comma... CVE-1999-0057 7.5 Vacation program allows command execution by remote users through a sendmail command.
View all Eric Allman CVEs →

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