How severe is CVE-2009-1534?

CVE-2009-1534 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-1534 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 52% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-1534?

CVE-2009-1534 primarily affects Microsoft Isa Server. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-1534?

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-2009-1534 published?

CVE-2009-1534 was published on 2009-08-12 and last updated on 2026-06-16.

CVE-2009-1534

CVE-2009-1534 is a critical-severity vulnerability in Microsoft Isa Server with a CVSS 2.0 base score of 9.3. Its EPSS exploit-prediction score of 52% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 52% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Microsoft Isa Server
Published: 2009-08-12
Last modified: 2026-06-16

Description

Buffer overflow in the Office Web Components ActiveX Control in Microsoft Office XP SP3, Office 2000 Web Components SP3, Office XP Web Components SP3, BizTalk Server 2002, and Visual Studio .NET 2003 SP1 allows remote attackers to execute arbitrary code via crafted property values, aka "Office Web Components Buffer Overflow Vulnerability."

Frequently asked questions

What is CVE-2009-1534?: Buffer overflow in the Office Web Components ActiveX Control in Microsoft Office XP SP3, Office 2000 Web Components SP3, Office XP Web Components SP3, BizTalk Server 2002, and Visual Studio .NET 2003 SP1 allows remote attackers to execute arbitrary code via crafted property values, aka "Office Web Components Buffer Overflow Vulnerability."
How severe is CVE-2009-1534?: CVE-2009-1534 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-1534 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 52% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-1534?: CVE-2009-1534 primarily affects Microsoft Isa Server. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-1534?: 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-2009-1534 published?: CVE-2009-1534 was published on 2009-08-12 and last updated on 2026-06-16.

References

Affected products (11)

cpe:2.3:a:microsoft:isa_server:2004:sp3:enterprise:*:*:*:*:*
cpe:2.3:a:microsoft:isa_server:2004:sp3:standard:*:*:*:*:*
cpe:2.3:a:microsoft:isa_server:2006:sp1:enterprise:*:*:*:*:*
cpe:2.3:a:microsoft:isa_server:2006:sp1:standard:*:*:*:*:*
cpe:2.3:a:microsoft:office:-:*:small_business_accounting_2006:*:*:*:*:*
cpe:2.3:a:microsoft:office:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:xp:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_web_components:2000:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_web_components:2003:sp1:2007_microsoft_office:*:*:*:*:*
cpe:2.3:a:microsoft:office_web_components:2003:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_web_components:xp:sp3:*:*:*:*:*:*

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