How severe is CVE-1999-0203?

CVE-1999-0203 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-1999-0203 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-0203?

CVE-1999-0203 affects Eric Allman Sendmail. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-1999-0203?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-1999-0203 published?

CVE-1999-0203 was published on 1995-08-17 and last updated on 2026-06-16.

CVE-1999-0203

CVE-1999-0203 is a critical-severity vulnerability in Eric Allman Sendmail with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Eric Allman Sendmail
Published: 1995-08-17
Last modified: 2026-06-16

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.

Frequently asked questions

What is CVE-1999-0203?: 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.
How severe is CVE-1999-0203?: CVE-1999-0203 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-1999-0203 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-0203?: CVE-1999-0203 affects Eric Allman Sendmail. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-1999-0203?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-1999-0203 published?: CVE-1999-0203 was published on 1995-08-17 and last updated on 2026-06-16.

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0203

Affected products (1)

cpe:2.3:a:eric_allman:sendmail:8.6.10:*:*:*:*:*:*:*

More vulnerabilities in Eric Allman Sendmail

CVE-1999-0047 — Critical (CVSS 10.0): MIME conversion buffer overflow in sendmail versions 8.8.3 and 8.8.4.
CVE-1999-0204 — Critical (CVSS 10.0): Sendmail 8.6.9 allows remote attackers to execute root commands, using ident.
CVE-1999-0206 — Critical (CVSS 10.0): MIME buffer overflow in Sendmail 8.8.0 and 8.8.1 gives root access.
CVE-1999-0095 — Critical (CVSS 10.0): The debug command in Sendmail is enabled, allowing attackers to execute commands as root.
CVE-1999-0163 — High (CVSS 7.2): In older versions of Sendmail, an attacker could use a pipe character to execute root commands.
CVE-1999-0130 — High (CVSS 7.2): Local users can start Sendmail in daemon mode and gain root privileges.

All CVEs affecting Eric Allman Sendmail →