How severe is CVE-2009-2043?

CVE-2009-2043 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2009-2043 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2043?

CVE-2009-2043 primarily affects Mozilla Firefox. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2043?

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

When was CVE-2009-2043 published?

CVE-2009-2043 was published on 2009-06-12 and last updated on 2026-06-16.

CVE-2009-2043

CVE-2009-2043 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 4.3. 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: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Firefox
Published: 2009-06-12
Last modified: 2026-06-16

Description

nsViewManager.cpp in Mozilla Firefox 3.0.2 through 3.0.10 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via vectors related to interaction with TinyMCE.

Frequently asked questions

What is CVE-2009-2043?: nsViewManager.cpp in Mozilla Firefox 3.0.2 through 3.0.10 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via vectors related to interaction with TinyMCE.
How severe is CVE-2009-2043?: CVE-2009-2043 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2009-2043 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-2043?: CVE-2009-2043 primarily affects Mozilla Firefox. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-2043?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-2043 published?: CVE-2009-2043 was published on 2009-06-12 and last updated on 2026-06-16.

References

Affected products (9)

cpe:2.3:a:mozilla:firefox:3.0.2:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.3:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.4:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.5:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.6:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.7:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.8:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.9:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:3.0.10:*:*:*:*:*:*:*

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