CVE-2003-0681: A "potential buffer overflow in ruleset parsing" for Sendmail 8.12.9, when using the nonstandard rulesets (1)

This week

HIGH 7.5DOWNGRADEDOWNGRADEDOWNGRADE

CVE-2003-0681 is a high-severity flaw (CVSS 7.5) affecting advanced message server, sendmail, sendmail pro. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A "potential buffer overflow in ruleset parsing" for Sendmail 8.12.9, when using the nonstandard rulesets (1) recipient (2), final, or (3) mailer-specific envelope recipients, has unknown consequences.

Why this priority

High severity
EPSS top 2%: very likely to be exploited
Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	22.4% (top 2%)
CISA exploited list	No
Published	2003-10-06
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: apple · sendmail

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2003-10-06 04:00 UTCPublished CVE record published
2026-06-16 22:02 UTCUpdated Record last modified

sendmail advanced message server DOWNGRADE

Affected: 1.2 · 1.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.2

1. Check installed version

apt-cache policy advanced-message-server || rpm -q advanced-message-server || advanced-message-server --version

2. No fixed release: DOWNGRADE to a release before 1.2 (Debian / Ubuntu)

apt-cache madison advanced-message-server sudo apt install advanced-message-server=<VERSION_BEFORE_1.2> sudo apt-mark hold advanced-message-server

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list advanced-message-server sudo dnf downgrade advanced-message-server-<VERSION_BEFORE_1.2> sudo dnf versionlock add advanced-message-server

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

sendmail sendmail DOWNGRADE

Affected: 2.6 · 2.6.1 · 2.6.2 · 3.0 · 3.0.1 · 3.0.2 · 3.0.3 · 8.8.8

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.6

1. Check installed version

apt-cache policy sendmail || rpm -q sendmail || sendmail --version

2. No fixed release: DOWNGRADE to a release before 2.6 (Debian / Ubuntu)

apt-cache madison sendmail sudo apt install sendmail=<VERSION_BEFORE_2.6> sudo apt-mark hold sendmail

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list sendmail sudo dnf downgrade sendmail-<VERSION_BEFORE_2.6> sudo dnf versionlock add sendmail

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

sendmail sendmail pro DOWNGRADE

Affected: 8.9.2 · 8.9.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.9.2

1. Check installed version

apt-cache policy sendmail-pro || rpm -q sendmail-pro || sendmail-pro --version

2. No fixed release: DOWNGRADE to a release before 8.9.2 (Debian / Ubuntu)

apt-cache madison sendmail-pro sudo apt install sendmail-pro=<VERSION_BEFORE_8.9.2> sudo apt-mark hold sendmail-pro

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list sendmail-pro sudo dnf downgrade sendmail-pro-<VERSION_BEFORE_8.9.2> sudo dnf versionlock add sendmail-pro

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

sendmail sendmail switch DOWNGRADE

Affected: 2.1 · 2.1.1 · 2.1.2 · 2.1.3 · 2.1.4 · 2.1.5 · 2.2 · 2.2.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.1

1. Check installed version

apt-cache policy sendmail-switch || rpm -q sendmail-switch || sendmail-switch --version

2. No fixed release: DOWNGRADE to a release before 2.1 (Debian / Ubuntu)

apt-cache madison sendmail-switch sudo apt install sendmail-switch=<VERSION_BEFORE_2.1> sudo apt-mark hold sendmail-switch

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list sendmail-switch sudo dnf downgrade sendmail-switch-<VERSION_BEFORE_2.1> sudo dnf versionlock add sendmail-switch

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

apple mac os x MITIGATE

Affected: 10.2 · 10.2.1 · 10.2.2 · 10.2.3 · 10.2.4 · 10.2.5 · 10.2.6

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.2

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

apple mac os x server MITIGATE

Affected: 10.2 · 10.2.1 · 10.2.2 · 10.2.3 · 10.2.4 · 10.2.5 · 10.2.6

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.2

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: Sendmail 8.12.9 - 'Prescan()' Variant Remote Buffer Overrun

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2003-0681?

advanced message server: downgrade or apply the listed mitigation; sendmail: downgrade or apply the listed mitigation; sendmail pro: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2003-0681 being exploited?

CVE-2003-0681 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2003-0681 affect?

CVE-2003-0681 affects advanced message server, sendmail, sendmail pro. Severity is high (CVSS 7.5). A "potential buffer overflow in ruleset parsing" for Sendmail 8.12.9, when using the nonstandard rulesets (1) recipient (2), final, or (3) mailer-specific envelope recipients, has unknown consequences.

How urgent is CVE-2003-0681?

Priority 56/100. High severity; EPSS top 2%: very likely to be exploited; Public exploit reference

Related CVEs

CVE-2003-0694 HIGH 10.0 DOWNGRADE DOWNGRADE The prescan function in Sendmail 8.12.9 allows remote attackers to execute arbitrary code via buffer overflow

References

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