Is CVE-2011-0421 in the CISA KEV catalog?

No. CVE-2011-0421 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2011-0421?

CVE-2011-0421 has a CVSS v2 base score of 4.3 (MEDIUM).

What is the EPSS score for CVE-2011-0421?

CVE-2011-0421 has an EPSS score of 13.51% (96th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2011-0421

MEDIUMEPSS 96th pctl

4.3

CVSS v2

NVD

Description

The _zip_name_locate function in zip_name_locate.c in the Zip extension in PHP before 5.3.6 does not properly handle a ZIPARCHIVE::FL_UNCHANGED argument, which might allow context-dependent attackers to cause a denial of service (NULL pointer dereference) via an empty ZIP archive that is processed with a (1) locateName or (2) statName operation.

CVSS v2 Vector

No CVSS vector data available.

Exploit Intelligence

13.51%probability of exploitation in 30 days

96thpercentile

Very high risk: more likely to be exploited than 96% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-29.