How severe is CVE-2012-4435?

CVE-2012-4435 has a CVSS 2.0 base score of 4.0, rated medium severity.

Is CVE-2012-4435 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-4435?

CVE-2012-4435 primarily affects Cipherdyne Fwknop. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-4435?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2012-4435 published?

CVE-2012-4435 was published on 2012-10-22 and last updated on 2026-06-16.

CVE-2012-4435

CVE-2012-4435 is a medium-severity vulnerability in Cipherdyne Fwknop with a CVSS 2.0 base score of 4.0. 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: Medium (CVSS 2.0 base score 4.0)
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cipherdyne Fwknop
Published: 2012-10-22
Last modified: 2026-06-16

Description

fwknop before 2.0.3 does not properly validate IP addresses, which allows remote authenticated users to cause a denial of service (server crash) via a long IP address.

Frequently asked questions

What is CVE-2012-4435?: fwknop before 2.0.3 does not properly validate IP addresses, which allows remote authenticated users to cause a denial of service (server crash) via a long IP address.
How severe is CVE-2012-4435?: CVE-2012-4435 has a CVSS 2.0 base score of 4.0, rated medium severity.
Is CVE-2012-4435 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-4435?: CVE-2012-4435 primarily affects Cipherdyne Fwknop. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-4435?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-4435 published?: CVE-2012-4435 was published on 2012-10-22 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:a:cipherdyne:fwknop:*:*:*:*:*:*:*:*
cpe:2.3:a:cipherdyne:fwknop:2.0:*:*:*:*:*:*:*
cpe:2.3:a:cipherdyne:fwknop:2.0.1:*:*:*:*:*:*:*

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CVE-2012-4434 — High (CVSS 8.8): fwknop before 2.0.3 allow remote authenticated users to cause a denial of service (server crash) or possibly execute…
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