How severe is CVE-2006-5974?

CVE-2006-5974 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2006-5974 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-5974?

CVE-2006-5974 primarily affects Fetchmail. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2006-5974?

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-2006-5974 published?

CVE-2006-5974 was published on 2006-12-31 and last updated on 2026-06-16.

CVE-2006-5974

CVE-2006-5974 is a high-severity vulnerability in Fetchmail with a CVSS 2.0 base score of 7.8. 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 7.8)
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Fetchmail
Published: 2006-12-31
Last modified: 2026-06-16

Description

fetchmail 6.3.5 and 6.3.6 before 6.3.6-rc4, when refusing a message delivered via the mda option, allows remote attackers to cause a denial of service (crash) via unknown vectors that trigger a NULL pointer dereference when calling the (1) ferror or (2) fflush functions.

Frequently asked questions

What is CVE-2006-5974?: fetchmail 6.3.5 and 6.3.6 before 6.3.6-rc4, when refusing a message delivered via the mda option, allows remote attackers to cause a denial of service (crash) via unknown vectors that trigger a NULL pointer dereference when calling the (1) ferror or (2) fflush functions.
How severe is CVE-2006-5974?: CVE-2006-5974 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2006-5974 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-5974?: CVE-2006-5974 primarily affects Fetchmail. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2006-5974?: 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-2006-5974 published?: CVE-2006-5974 was published on 2006-12-31 and last updated on 2026-06-16.

References

Affected products (4)

cpe:2.3:a:fetchmail:fetchmail:6.3.5:*:*:*:*:*:*:*
cpe:2.3:a:fetchmail:fetchmail:6.3.6:rc1:*:*:*:*:*:*
cpe:2.3:a:fetchmail:fetchmail:6.3.6:rc2:*:*:*:*:*:*
cpe:2.3:a:fetchmail:fetchmail:6.3.6:rc3:*:*:*:*:*:*

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