How severe is CVE-2011-2631?

CVE-2011-2631 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2011-2631 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-2631?

CVE-2011-2631 primarily affects Opera Opera Browser. In total, 118 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-2631?

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

When was CVE-2011-2631 published?

CVE-2011-2631 was published on 2011-07-01 and last updated on 2026-06-16.

CVE-2011-2631

CVE-2011-2631 is a medium-severity vulnerability in Opera Opera Browser with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Opera Opera Browser
Published: 2011-07-01
Last modified: 2026-06-16

Description

The Cascading Style Sheets (CSS) implementation in Opera before 11.11 does not properly handle the column-count property, which allows remote attackers to cause a denial of service (infinite repaint loop and application hang) via a web page, as demonstrated by an unspecified Wikipedia page.

Frequently asked questions

What is CVE-2011-2631?: The Cascading Style Sheets (CSS) implementation in Opera before 11.11 does not properly handle the column-count property, which allows remote attackers to cause a denial of service (infinite repaint loop and application hang) via a web page, as demonstrated by an unspecified Wikipedia page.
How severe is CVE-2011-2631?: CVE-2011-2631 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2011-2631 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2631?: CVE-2011-2631 primarily affects Opera Opera Browser. In total, 118 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-2631?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-2631 published?: CVE-2011-2631 was published on 2011-07-01 and last updated on 2026-06-16.

References

Affected products (118)

cpe:2.3:a:opera:opera_browser:*:*:*:*:*:*:*:*
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:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:beta2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:tp1:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:tp2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.0:tp3:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.1:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.01:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.1:beta1:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.02:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.03:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.04:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.05:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.06:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.11:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:6.12:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.0:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.0:beta1:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.0:beta1_v2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.0:beta2:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.01:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.02:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.03:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.10:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.10:beta1:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.11:*:*:*:*:*:*:*
cpe:2.3:a:opera:opera_browser:7.11:beta2:*:*:*:*:*:*

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