How severe is CVE-2011-0082?

CVE-2011-0082 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2011-0082 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-0082?

CVE-2011-0082 primarily affects Mozilla Firefox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-0082?

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

When was CVE-2011-0082 published?

CVE-2011-0082 was published on 2011-06-06 and last updated on 2026-06-16.

CVE-2011-0082

CVE-2011-0082 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: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mozilla Firefox
Published: 2011-06-06
Last modified: 2026-06-16

Description

The X.509 certificate validation functionality in Mozilla Firefox 4.0.x through 4.0.1 does not properly implement single-session security exceptions, which might make it easier for user-assisted remote attackers to spoof an SSL server via an untrusted certificate that triggers potentially unwanted local caching of documents from that server.

Frequently asked questions

What is CVE-2011-0082?: The X.509 certificate validation functionality in Mozilla Firefox 4.0.x through 4.0.1 does not properly implement single-session security exceptions, which might make it easier for user-assisted remote attackers to spoof an SSL server via an untrusted certificate that triggers potentially unwanted local caching of documents from that server.
How severe is CVE-2011-0082?: CVE-2011-0082 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2011-0082 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-0082?: CVE-2011-0082 primarily affects Mozilla Firefox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-0082?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-0082 published?: CVE-2011-0082 was published on 2011-06-06 and last updated on 2026-06-16.

References

Affected products (14)

cpe:2.3:a:mozilla:firefox:4.0:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta1:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta10:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta11:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta12:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta2:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta3:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta4:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta5:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta6:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta7:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta8:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0:beta9:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:4.0.1:*:*:*:*:*:*:*

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