CVE-2003-0101: miniserv.pl in (1) Webmin before 1.070 and (2) Usermin before 1.000 does not properly handle metacharacters su

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HIGH 10.0WATCHLISTDOWNGRADEDOWNGRADEDOWNGRADE

CVE-2003-0101 is a high-severity flaw (CVSS 10.0) affecting guardian digital webtool, usermin, webmin. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

miniserv.pl in (1) Webmin before 1.070 and (2) Usermin before 1.000 does not properly handle metacharacters such as line feeds and carriage returns (CRLF) in Base-64 encoded strings during Basic authentication, which allows remote attackers to spoof a session ID and gain root privileges.

Why this priority

Critical severity
EPSS top 3%: very likely to be exploited
Public exploit reference
On your watchlist

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

Risk facts

CVSS score	10.0 (High)
EPSS exploit chance	15.5% (top 3%)
CISA exploited list	No
Published	2003-03-03
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: engardelinux · usermin · webmin

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

Am I affected?

Timeline

2003-03-03 05:00 UTCPublished CVE record published
2026-06-16 22:01 UTCUpdated Record last modified

engardelinux guardian digital webtool DOWNGRADE

Affected: 1.2

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.2

1. Check installed version

apt-cache policy guardian-digital-webtool || rpm -q guardian-digital-webtool || guardian-digital-webtool --version

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

apt-cache madison guardian-digital-webtool sudo apt install guardian-digital-webtool=<VERSION_BEFORE_1.2> sudo apt-mark hold guardian-digital-webtool

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

dnf --showduplicates list guardian-digital-webtool sudo dnf downgrade guardian-digital-webtool-<VERSION_BEFORE_1.2> sudo dnf versionlock add guardian-digital-webtool

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.

usermin usermin DOWNGRADE

Affected: 0.4 · 0.5 · 0.6 · 0.7 · 0.8 · 0.9 · 0.91 · 0.92

Fixed in: no fixed release known

Safe to downgrade to: a release before 0.4

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 0.4 (Debian / Ubuntu)

apt-cache madison usermin sudo apt install usermin=<VERSION_BEFORE_0.4> sudo apt-mark hold usermin

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

dnf --showduplicates list usermin sudo dnf downgrade usermin-<VERSION_BEFORE_0.4> sudo dnf versionlock add usermin

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.

webmin webmin DOWNGRADE

Affected: 1.0.50 · 1.0.60

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.0.50

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 1.0.50 (Debian / Ubuntu)

apt-cache madison webmin sudo apt install webmin=<VERSION_BEFORE_1.0.50> sudo apt-mark hold webmin

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

dnf --showduplicates list webmin sudo dnf downgrade webmin-<VERSION_BEFORE_1.0.50> sudo dnf versionlock add webmin

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.

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: Webmin 0.9x / Usermin 0.9x/1.0 - Access Session ID Spoofing

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-2003-0101?

guardian digital webtool: downgrade or apply the listed mitigation; usermin: downgrade or apply the listed mitigation; webmin: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2003-0101 being exploited?

CVE-2003-0101 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-2003-0101 affect?

CVE-2003-0101 affects guardian digital webtool, usermin, webmin. Severity is high (CVSS 10.0). miniserv.pl in (1) Webmin before 1.070 and (2) Usermin before 1.000 does not properly handle metacharacters such as line feeds and carriage returns (CRLF) in Base-64 encoded strings during Basic authentication, which allows remote attackers

How urgent is CVE-2003-0101?

Priority 69/100. Critical severity; EPSS top 3%: very likely to be exploited; Public exploit reference; On your watchlist

References

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