How severe is CVE-2001-0427?

CVE-2001-0427 has a CVSS 2.0 base score of 7.1, rated high severity.

Is CVE-2001-0427 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2001-0427?

CVE-2001-0427 primarily affects Cisco Vpn 3000 Concentrator. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2001-0427?

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

When was CVE-2001-0427 published?

CVE-2001-0427 was published on 2001-06-18 and last updated on 2026-06-16.

CVE-2001-0427

CVE-2001-0427 is a high-severity vulnerability in Cisco Vpn 3000 Concentrator with a CVSS 2.0 base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 2.0 base score 7.1)
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Vpn 3000 Concentrator
Published: 2001-06-18
Last modified: 2026-06-16

Description

Cisco VPN 3000 series concentrators before 2.5.2(F) allow remote attackers to cause a denial of service via a flood of invalid login requests to (1) the SSL service, or (2) the telnet service, which do not properly disconnect the user after several failed login attempts.

Frequently asked questions

What is CVE-2001-0427?: Cisco VPN 3000 series concentrators before 2.5.2(F) allow remote attackers to cause a denial of service via a flood of invalid login requests to (1) the SSL service, or (2) the telnet service, which do not properly disconnect the user after several failed login attempts.
How severe is CVE-2001-0427?: CVE-2001-0427 has a CVSS 2.0 base score of 7.1, rated high severity.
Is CVE-2001-0427 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2001-0427?: CVE-2001-0427 primarily affects Cisco Vpn 3000 Concentrator. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2001-0427?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2001-0427 published?: CVE-2001-0427 was published on 2001-06-18 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:h:cisco:vpn_3000_concentrator:*:*:*:*:*:*:*:*
cpe:2.3:h:cisco:vpn_3005_concentrator:*:*:*:*:*:*:*:*
cpe:2.3:h:cisco:vpn_3015_concentrator:*:*:*:*:*:*:*:*
cpe:2.3:h:cisco:vpn_3030_concentator:*:*:*:*:*:*:*:*
cpe:2.3:h:cisco:vpn_3060_concentrator:*:*:*:*:*:*:*:*
cpe:2.3:h:cisco:vpn_3080_concentrator:*:*:*:*:*:*:*:*

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