How severe is CVE-2009-4629?

CVE-2009-4629 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-4629 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-4629?

CVE-2009-4629 primarily affects Mozilla Seamonkey. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-4629?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2009-4629 published?

CVE-2009-4629 was published on 2010-01-29 and last updated on 2026-06-16.

CVE-2009-4629

CVE-2009-4629 is a medium-severity vulnerability in Mozilla Seamonkey with a CVSS 2.0 base score of 5.0. 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-200.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Mozilla Seamonkey
Published: 2010-01-29
Last modified: 2026-06-16

Description

Mozilla Necko, as used in Thunderbird 3.0.1, SeaMonkey, and other applications, performs DNS prefetching even when the app type is APP_TYPE_MAIL or APP_TYPE_EDITOR, which makes it easier for remote attackers to determine the network location of the application's user by logging DNS requests, as demonstrated by DNS requests triggered by reading text/plain e-mail messages in Thunderbird.

Frequently asked questions

What is CVE-2009-4629?: Mozilla Necko, as used in Thunderbird 3.0.1, SeaMonkey, and other applications, performs DNS prefetching even when the app type is APP_TYPE_MAIL or APP_TYPE_EDITOR, which makes it easier for remote attackers to determine the network location of the application's user by logging DNS requests, as demonstrated by DNS requests triggered by reading text/plain e-mail messages in Thunderbird.
How severe is CVE-2009-4629?: CVE-2009-4629 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-4629 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4629?: CVE-2009-4629 primarily affects Mozilla Seamonkey. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-4629?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-4629 published?: CVE-2009-4629 was published on 2010-01-29 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:3.0.1:*:*:*:*:*:*:*

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