CVE-2011-4957

CVE-2011-4957 is a medium-severity vulnerability in Wordpress 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

Description

The make_clickable function in wp-includes/formatting.php in WordPress before 3.1.1 does not properly check URLs before passing them to the PCRE library, which allows remote attackers to cause a denial of service (crash) via a comment with a crafted URL that triggers many recursive calls.

Frequently asked questions

What is CVE-2011-4957?
The make_clickable function in wp-includes/formatting.php in WordPress before 3.1.1 does not properly check URLs before passing them to the PCRE library, which allows remote attackers to cause a denial of service (crash) via a comment with a crafted URL that triggers many recursive calls.
How severe is CVE-2011-4957?
CVE-2011-4957 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2011-4957 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4957?
CVE-2011-4957 primarily affects Wordpress. In total, 75 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-4957?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4957 published?
CVE-2011-4957 was published on 2012-06-27 and last updated on 2026-06-16.

References

Affected products (75)

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