How severe is CVE-2007-6521?

CVE-2007-6521 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2007-6521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-6521?

CVE-2007-6521 primarily affects Opera Opera Browser. In total, 102 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2007-6521?

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-2007-6521 published?

CVE-2007-6521 was published on 2007-12-24 and last updated on 2026-06-16.

CVE-2007-6521

CVE-2007-6521 is a critical-severity vulnerability in Opera Opera Browser with a CVSS 2.0 base score of 10.0. 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-310.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-310
Affected product: Opera Opera Browser
Published: 2007-12-24
Last modified: 2026-06-16

Description

Unspecified vulnerability in Opera before 9.25 allows remote attackers to execute arbitrary code via crafted TLS certificates.

Frequently asked questions

What is CVE-2007-6521?: Unspecified vulnerability in Opera before 9.25 allows remote attackers to execute arbitrary code via crafted TLS certificates.
How severe is CVE-2007-6521?: CVE-2007-6521 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2007-6521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-6521?: CVE-2007-6521 primarily affects Opera Opera Browser. In total, 102 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2007-6521?: 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-2007-6521 published?: CVE-2007-6521 was published on 2007-12-24 and last updated on 2026-06-16.

References

Affected products (102)

cpe:2.3:a:opera:opera_browser:*:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:1.00:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.00:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.10:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.10:beta1:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.10:beta2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.10:beta3:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:2.12:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.00:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.00:beta:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.10:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.21:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.50:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.51:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.60:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.61:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.62:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:3.62:beta:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:beta2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:beta3:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:beta4:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:beta5:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.00:beta6:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.01:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:4.02:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta3:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta4:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta5:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta6:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta7:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.0:beta8:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.02:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.10:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.11:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:5.12:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:beta1:*:*:*:*:*:*

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