CVE-2001-1444 — The Kerberos Telnet protocol, as implemented by KTH Kerberos IV and Kerberos V (Heimdal), does not encrypt authentication and encryption options sent from the server, which allows remote attackers to downgrade authentication and encryption mechanisms via a man-in-the-middle attack

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HIGH

The Kerberos Telnet protocol, as implemented by KTH Kerberos IV and Kerberos V (Heimdal), does not encrypt authentication and encryption options sent from the server, which allows remote attackers to downgrade authentication and encryption mechanisms via a man-in-the-middle attack

Published Apr 21, 2005

7.5

HIGH

CVSS 2.0

EPSS 1.30%

Description

The Kerberos Telnet protocol, as implemented by KTH Kerberos IV and Kerberos V (Heimdal), does not encrypt authentication and encryption options sent from the server, which allows remote attackers to downgrade authentication and encryption mechanisms via a man-in-the-middle attack.

Affected products

Remediation

No remediation recorded yet.

Metrics

1.30% 0.01296

Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.

EPSS probability 0.01296

Score over time

2022–2026

EPSS v2
EPSS v3
EPSS v4
EPSS v5

Percentile over time

EPSS v2
EPSS v3
EPSS v4
EPSS v5

Table of values (10 key points)

Flat stretches are collapsed; showing up to 120 newest points.

Date	Score	Percentile	Model
Oct 1, 2026	1.30% (0.01296)	69.31th	v5 (v2026.06.15)
Jun 15, 2026	1.30% (0.01296)	66.50th	v5 (v2026.06.15)
Mar 17, 2025	0.68% (0.00679)	69.86th	v4 (v2025.03.14)
Dec 12, 2024	0.60% (0.00599)	79.15th	v3 (v2023.03.01)
Feb 8, 2024	0.60% (0.00599)	77.75th	v3 (v2023.03.01)
Mar 7, 2023	0.60% (0.00599)	75.11th	v3 (v2023.03.01)
Mar 6, 2023	1.14% (0.01136)	59.45th	v2 (v2022.01.01)
Oct 18, 2022	1.14% (0.01136)	58.28th	v2 (v2022.01.01)
Apr 1, 2022	1.14% (0.01136)	56.27th	v2 (v2022.01.01)
Feb 4, 2022	1.14% (0.01136)	34.23th	v2 (v2022.01.01)

Weaknesses (0)

No CWE recorded.

References (3)

http://josefsson.org/ktelnet/kerberos-telnet.html
x_refsource_MISCExploit
http://www.kb.cert.org/vuls/id/774587
third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource
https://exchange.xforce.ibmcloud.com/vulnerabilities/10640
vdb-entryx_refsource_XF

Link	Providers	Tags
http://josefsson.org/ktelnet/kerberos-telnet.html		x_refsource_MISCExploit
http://www.kb.cert.org/vuls/id/774587		third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource
https://exchange.xforce.ibmcloud.com/vulnerabilities/10640		vdb-entryx_refsource_XF

Change history (0)

No recorded changes yet.

Sources

CVE.org / MITRE

Status PUBLISHED

Assigner mitre

Published Apr 21, 2005

Updated Aug 8, 2024

Reserved Apr 21, 2005

Link CVE-2001-1444

CISA Vulnrichment

Updated n/a

NVD

Status Modified

Modified Jun 16, 2026

Link CVE-2001-1444

Red Hat

Severity n/a

Public date n/a

Links CVE-2001-1444