How severe is CVE-2009-3831?

CVE-2009-3831 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2009-3831 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-3831?

CVE-2009-3831 affects Opera Opera Browser. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-3831?

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-2009-3831 published?

CVE-2009-3831 was published on 2009-10-30 and last updated on 2026-06-16.

CVE-2009-3831

CVE-2009-3831 is a critical-severity vulnerability in Opera Opera Browser 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-787.

Key facts

Severity: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Opera Opera Browser
Published: 2009-10-30
Last modified: 2026-06-16

Description

Opera before 10.01 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted domain name.

Frequently asked questions

What is CVE-2009-3831?: Opera before 10.01 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted domain name.
How severe is CVE-2009-3831?: CVE-2009-3831 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2009-3831 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-3831?: CVE-2009-3831 affects Opera Opera Browser. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-3831?: 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-2009-3831 published?: CVE-2009-3831 was published on 2009-10-30 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:opera:opera_browser:*:*:*:*:*:*:*:*

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