How severe is CVE-2009-0943?

CVE-2009-0943 has a CVSS 2.0 base score of 6.8, rated medium severity.

Is CVE-2009-0943 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-2009-0943?

CVE-2009-0943 primarily affects Apple Mac Os X. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-0943?

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

When was CVE-2009-0943 published?

CVE-2009-0943 was published on 2009-05-13 and last updated on 2026-06-16.

CVE-2009-0943

CVE-2009-0943 is a medium-severity vulnerability in Apple Mac Os X with a CVSS 2.0 base score of 6.8. 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 6.8)
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apple Mac Os X
Published: 2009-05-13
Last modified: 2026-06-16

Description

Help Viewer in Apple Mac OS X 10.4.11 and 10.5 before 10.5.7 does not verify that HTML pathnames are located in a registered help book, which allows remote attackers to execute arbitrary code via a help: URL that triggers invocation of AppleScript files.

Frequently asked questions

What is CVE-2009-0943?: Help Viewer in Apple Mac OS X 10.4.11 and 10.5 before 10.5.7 does not verify that HTML pathnames are located in a registered help book, which allows remote attackers to execute arbitrary code via a help: URL that triggers invocation of AppleScript files.
How severe is CVE-2009-0943?: CVE-2009-0943 has a CVSS 2.0 base score of 6.8, rated medium severity.
Is CVE-2009-0943 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-2009-0943?: CVE-2009-0943 primarily affects Apple Mac Os X. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-0943?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-0943 published?: CVE-2009-0943 was published on 2009-05-13 and last updated on 2026-06-16.

References

Affected products (16)

cpe:2.3:o:apple:mac_os_x:10.4.11:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.0:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.1:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.2:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.3:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.4:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.5:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.6:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.4.11:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.0:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.1:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.2:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.3:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.4:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.5:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.6:*:*:*:*:*:*:*

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