How severe is CVE-2007-0427?

CVE-2007-0427 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2007-0427 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-0427?

CVE-2007-0427 affects Microsoft Html Help Workshop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2007-0427?

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

When was CVE-2007-0427 published?

CVE-2007-0427 was published on 2007-01-23 and last updated on 2026-06-16.

CVE-2007-0427

CVE-2007-0427 is a critical-severity vulnerability in Microsoft Html Help Workshop with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 31% (98th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Html Help Workshop
Published: 2007-01-23
Last modified: 2026-06-16

Description

Stack-based buffer overflow in Microsoft Help Workshop 4.03.0002 allows user-assisted remote attackers to execute arbitrary code via a help project (.HPJ) file with a long HLP field in the OPTIONS section.

Frequently asked questions

What is CVE-2007-0427?: Stack-based buffer overflow in Microsoft Help Workshop 4.03.0002 allows user-assisted remote attackers to execute arbitrary code via a help project (.HPJ) file with a long HLP field in the OPTIONS section.
How severe is CVE-2007-0427?: CVE-2007-0427 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2007-0427 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-0427?: CVE-2007-0427 affects Microsoft Html Help Workshop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2007-0427?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2007-0427 published?: CVE-2007-0427 was published on 2007-01-23 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:microsoft:html_help_workshop:4.03.0002:*:*:*:*:*:*:*

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CVE-2009-0133 — Critical (CVSS 10.0): Buffer overflow in Microsoft HTML Help Workshop 4.74 and earlier allows context-dependent attackers to execute…
CVE-2007-0352 — Critical (CVSS 9.3): Stack-based buffer overflow in Microsoft Help Workshop 4.03.0002 allows user-assisted remote attackers to execute…
CVE-2006-0564 — High (CVSS 7.5): Stack-based buffer overflow in Microsoft HTML Help Workshop 4.74.8702.0, and possibly earlier versions, and as included…

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