CVE-2015-4021
MEDIUMEPSS 97th pctlDescription
The phar_parse_tarfile function in ext/phar/tar.c in PHP before 5.4.41, 5.5.x before 5.5.25, and 5.6.x before 5.6.9 does not verify that the first character of a filename is different from the \0 character, which allows remote attackers to cause a denial of service (integer underflow and memory corruption) via a crafted entry in a tar archive.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v2 Vector
No CVSS vector data available.
Exploit Intelligence
Very high risk: more likely to be exploited than 97% of all known CVEs.
References
Related Vulnerabilities
Other CWE-189 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2015-1538 | High | 10.0 | 99% | - | - |
| CVE-2006-3747 | High | 7.6 | 96% | - | Fix |
| CVE-2007-0071 | High | 9.3 | 93% | - | - |
| CVE-2015-3829 | High | 10.0 | 90% | - | - |
| CVE-2015-3864 | High | 10.0 | 87% | - | - |
| CVE-2015-1539 | High | 10.0 | 86% | - | - |
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Markdown
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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 2026-05-06.