How severe is CVE-2009-3866?

CVE-2009-3866 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-3866 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3866?

CVE-2009-3866 primarily affects Sun Jdk. In total, 31 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-3866?

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-2009-3866 published?

CVE-2009-3866 was published on 2009-11-05 and last updated on 2026-06-16.

CVE-2009-3866

CVE-2009-3866 is a critical-severity vulnerability in Sun Jdk 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-264.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-264
Affected product: Sun Jdk
Published: 2009-11-05
Last modified: 2026-06-16

Description

The Java Web Start Installer in Sun Java SE in JDK and JRE 6 before Update 17 does not properly use security model permissions when removing installer extensions, which allows remote attackers to execute arbitrary code by modifying a certain JNLP file to have a URL field that points to an unintended trusted application, aka Bug Id 6872824.

Frequently asked questions

What is CVE-2009-3866?: The Java Web Start Installer in Sun Java SE in JDK and JRE 6 before Update 17 does not properly use security model permissions when removing installer extensions, which allows remote attackers to execute arbitrary code by modifying a certain JNLP file to have a URL field that points to an unintended trusted application, aka Bug Id 6872824.
How severe is CVE-2009-3866?: CVE-2009-3866 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-3866 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3866?: CVE-2009-3866 primarily affects Sun Jdk. In total, 31 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-3866?: 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-2009-3866 published?: CVE-2009-3866 was published on 2009-11-05 and last updated on 2026-06-16.

References

Affected products (31)

cpe:2.3:a:sun:jdk:1.6.0:update_1:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_10:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_11:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_12:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_13:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_14:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_15:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_16:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_3:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_4:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_5:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_6:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_7:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_8:*:*:*:*:*:*
cpe:2.3:a:sun:jdk:1.6.0:update_9:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_1:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_10:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_11:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_12:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_13:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_14:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_15:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_16:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_2:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_3:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_4:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_5:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_6:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_7:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_8:*:*:*:*:*:*
cpe:2.3:a:sun:jre:1.6.0:update_9:*:*:*:*:*:*

More vulnerabilities in Sun Jdk

CVE-2013-5824 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, and Java SE Embedded 7u40 and…
CVE-2013-5817 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, Java SE 5.0u51 and earlier, and…
CVE-2013-5814 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, Java SE 5.0u51 and earlier, and…
CVE-2013-5809 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, Java SE 5.0u51 and earlier, and…
CVE-2013-5789 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, and Java SE Embedded 7u40 and…
CVE-2013-5787 — Critical (CVSS 10.0): Unspecified vulnerability in Oracle Java SE 7u40 and earlier, Java SE 6u60 and earlier, and Java SE Embedded 7u40 and…

All CVEs affecting Sun Jdk →

Other CWE-264 (Permissions, Privileges, and Access Controls) vulnerabilities

CVE-2016-8363 — Critical (CVSS 10.0): An issue was discovered in Moxa OnCell OnCellG3470A-LTE, AWK-1131A/3131A/4131A Series, AWK-3191 Series, AWK-5232/6232…
CVE-2016-7457 — Critical (CVSS 10.0): VMware vRealize Operations (aka vROps) 6.x before 6.4.0 allows remote authenticated users to gain privileges, or halt…
CVE-2015-7425 — Critical (CVSS 10.0): The Data Protection component in the VMware vSphere GUI in IBM Tivoli Storage Manager for Virtual Environments: Data…
CVE-2015-8267 — Critical (CVSS 10.0): The PasswordReset.Controllers.ResetController.ChangePasswordIndex method in PasswordReset.dll in Dovestones AD Self…
CVE-2015-7919 — Critical (CVSS 10.0): SearchBlox 8.3 before 8.3.1 allows remote attackers to write to the config file, and consequently cause a denial of…
CVE-2015-7071 — Critical (CVSS 10.0): The File Bookmark component in Apple OS X before 10.11.2 allows attackers to bypass a sandbox protection mechanism for…

Browse all CWE-264 (Permissions, Privileges, and Access Controls) vulnerabilities →