How severe is CVE-2007-6573?

CVE-2007-6573 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2007-6573 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-6573?

CVE-2007-6573 affects Qksoft Qk Smtp Server 3. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2007-6573?

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-2007-6573 published?

CVE-2007-6573 was published on 2007-12-28 and last updated on 2026-06-16.

CVE-2007-6573

CVE-2007-6573 is a high-severity vulnerability in Qksoft Qk Smtp Server 3 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: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Qksoft Qk Smtp Server 3
Published: 2007-12-28
Last modified: 2026-06-16

Description

QK SMTP Server 3 allows remote attackers to cause a denial of service (daemon crash) via a long (1) HELO, (2) MAIL FROM, or (3) RCPT TO command; or (4) a long string in the message sent after the DATA command; possibly a related issue to CVE-2006-5551.

Frequently asked questions

What is CVE-2007-6573?: QK SMTP Server 3 allows remote attackers to cause a denial of service (daemon crash) via a long (1) HELO, (2) MAIL FROM, or (3) RCPT TO command; or (4) a long string in the message sent after the DATA command; possibly a related issue to CVE-2006-5551.
How severe is CVE-2007-6573?: CVE-2007-6573 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2007-6573 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-6573?: CVE-2007-6573 affects Qksoft Qk Smtp Server 3. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2007-6573?: 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-2007-6573 published?: CVE-2007-6573 was published on 2007-12-28 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:qksoft:qk_smtp_server_3:*:*:*:*:*:*:*:*

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