How severe is CVE-2009-1491?

CVE-2009-1491 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-1491 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-1491?

CVE-2009-1491 affects Mcafee Groupshield. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-1491?

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-2009-1491 published?

CVE-2009-1491 was published on 2009-05-05 and last updated on 2026-06-16.

CVE-2009-1491

CVE-2009-1491 is a critical-severity vulnerability in Mcafee Groupshield with a CVSS 2.0 base score of 9.3. 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: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mcafee Groupshield
Published: 2009-05-05
Last modified: 2026-06-16

Description

McAfee GroupShield for Microsoft Exchange on Exchange Server 2000, and possibly other anti-virus or anti-spam products from McAfee or other vendors, does not scan X- headers for malicious content, which allows remote attackers to bypass virus detection via a crafted message, as demonstrated by a message with an X-Testing header and no message body.

Frequently asked questions

What is CVE-2009-1491?: McAfee GroupShield for Microsoft Exchange on Exchange Server 2000, and possibly other anti-virus or anti-spam products from McAfee or other vendors, does not scan X- headers for malicious content, which allows remote attackers to bypass virus detection via a crafted message, as demonstrated by a message with an X-Testing header and no message body.
How severe is CVE-2009-1491?: CVE-2009-1491 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-1491 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-1491?: CVE-2009-1491 affects Mcafee Groupshield. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-1491?: 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-2009-1491 published?: CVE-2009-1491 was published on 2009-05-05 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:mcafee:groupshield:*:*:*:*:*:*:*:*

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