CVE-2000-0391

CRITICAL

Buffer overflow in krshd in Kerberos 5 allows remote attackers to gain root privileges.

Affects 5 products across 3 vendors.

CVSS 2.010.0
EPSS4.0%
Percentile91th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity.
◆ AI Analysis — automated analysis, not human-reviewed

This vulnerability was disclosed in 2000. A critical vulnerability affects Cygnus systems (CVE-2000-0391). No public exploit code is currently available. Isolate affected systems if patching is not feasible.

BSID: BS-2000-GLOBAL-349423-C • Model: rule-based-v1 • Confidence: MEDIUM

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Frequently Asked Questions
What is CVE-2000-0391?
This vulnerability was disclosed in 2000. A critical vulnerability affects Cygnus systems (CVE-2000-0391). No public exploit code is currently available. Isolate affected systems if patching is not feasible.
What is the CVSS score for CVE-2000-0391?
CVE-2000-0391 has CVSS 10.0 (Critical). Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C. EPSS: 4.0%.
Is CVE-2000-0391 actively exploited?
No confirmed active exploitation of CVE-2000-0391 as of 2026-06-20.
How do I remediate CVE-2000-0391?
Priority: MEDIUM.
What systems are affected by CVE-2000-0391?
CVE-2000-0391 affects Cygnus Cygnus Network Security, Kerbnet; Mit Kerberos, Kerberos 5; Redhat Linux.
Vulnerability Details
CVE IDCVE-2000-0391
BSIDBS-2000-GLOBAL-349423-C BreachSpider Global ID
CVSS VectorAV:N/AC:L/Au:N/C:C/I:C/A:C
Published2000-05-16
Last Modified2026-06-16
ICS Relevance0%
SourceNVD
Official Description

Buffer overflow in krshd in Kerberos 5 allows remote attackers to gain root privileges.

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

Vulnerability details: Buffer overflow in krshd in Kerberos 5 allows remote attackers to gain root privileges. CVSS vector: AV:N/AC:L/Au:N/C:C/I:C/A:C.

Exploitation Likelihood: LOW

Affected Products
VendorProductAffected Versions
Cygnus Cygnus Network Security 4.0
Cygnus Kerbnet 5.0
Mit Kerberos 4.0
Mit Kerberos 5 1.0 1.1.1 4.0
Redhat Linux 6.2
Remediation

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

Threat Intelligence
● Threat Intelligence Validated: October 2026 | Threat Age: 9657 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 Hash7afadb410f2c41d685d29cd10940ec0d15922c4a9bb5e14c0e83f5641d387336e432b3e5e86a8949a13e93be9b28c349b7a7aad164cabfe10874213e3762adcc
Related CVEs affecting Cygnus
CVE-2000-0389 10.0 Buffer overflow in krb_rd_req function in Kerberos 4 and 5 allows remote atta... CVE-2000-0390 10.0 Buffer overflow in krb425_conv_principal function in Kerberos 5 allows remote... CVE-2000-0392 7.2 Buffer overflow in ksu in Kerberos 5 allows local users to gain root privileges. CVE-2000-0549 5.0 Kerberos 4 KDC program does not properly check for null termination of AUTH_M... CVE-2000-0550 5.0 Kerberos 4 KDC program improperly frees memory twice (aka "double-free"), whi...
View all Cygnus CVEs →

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