How severe is CVE-2009-4102?

CVE-2009-4102 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-4102 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-4102?

CVE-2009-4102 primarily affects Sage.mozdev Sage. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-4102?

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-2009-4102 published?

CVE-2009-4102 was published on 2009-11-29 and last updated on 2026-06-16.

CVE-2009-4102

CVE-2009-4102 is a critical-severity vulnerability in Sage.mozdev Sage 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% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Sage.mozdev Sage
Published: 2009-11-29
Last modified: 2026-06-16

Description

Sage 1.4.3 and earlier extension for Firefox performs certain operations with chrome privileges, which allows remote attackers to execute arbitrary commands and perform cross-domain scripting attacks via the description tag of an RSS feed.

Frequently asked questions

What is CVE-2009-4102?: Sage 1.4.3 and earlier extension for Firefox performs certain operations with chrome privileges, which allows remote attackers to execute arbitrary commands and perform cross-domain scripting attacks via the description tag of an RSS feed.
How severe is CVE-2009-4102?: CVE-2009-4102 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-4102 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4102?: CVE-2009-4102 primarily affects Sage.mozdev Sage. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-4102?: 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-2009-4102 published?: CVE-2009-4102 was published on 2009-11-29 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:a:sage.mozdev:sage:*:*:*:*:*:*:*:*
cpe:2.3:a:sage.mozdev:sage:1.3.8:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

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