How severe is CVE-2013-4338?

CVE-2013-4338 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2013-4338 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-4338?

CVE-2013-4338 affects Wordpress. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2013-4338?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2013-4338 published?

CVE-2013-4338 was published on 2013-09-12 and last updated on 2026-06-16.

CVE-2013-4338

CVE-2013-4338 is a high-severity vulnerability in Wordpress with a CVSS 2.0 base score of 7.5. 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-94.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 9% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Wordpress
Published: 2013-09-12
Last modified: 2026-06-16

Description

wp-includes/functions.php in WordPress before 3.6.1 does not properly determine whether data has been serialized, which allows remote attackers to execute arbitrary code by triggering erroneous PHP unserialize operations.

Frequently asked questions

What is CVE-2013-4338?: wp-includes/functions.php in WordPress before 3.6.1 does not properly determine whether data has been serialized, which allows remote attackers to execute arbitrary code by triggering erroneous PHP unserialize operations.
How severe is CVE-2013-4338?: CVE-2013-4338 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2013-4338 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-4338?: CVE-2013-4338 affects Wordpress. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2013-4338?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2013-4338 published?: CVE-2013-4338 was published on 2013-09-12 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*

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