CVE-2015-4021

CVE-2015-4021 is a medium-severity vulnerability in Php with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 21% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-189.

Key facts

• Severity: Medium (CVSS 2.0 base score 5.0)
• EPSS exploit prediction: 21% (97th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-189
• Affected product: Php
• Published: 2015-06-09
• Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2015-4021?

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 severe is CVE-2015-4021?

CVE-2015-4021 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2015-4021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 21% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-4021?

CVE-2015-4021 primarily affects Php. In total, 61 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-4021?

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

When was CVE-2015-4021 published?

CVE-2015-4021 was published on 2015-06-09 and last updated on 2026-06-17.

References

• http://lists.apple.com/archives/security-announce/2015/Aug/msg00001.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-May/158616.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-May/158915.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-May/159031.html
• http://lists.opensuse.org/opensuse-updates/2015-06/msg00002.html
• http://php.net/ChangeLog-5.php
• http://rhn.redhat.com/errata/RHSA-2015-1135.html
• http://rhn.redhat.com/errata/RHSA-2015-1186.html
• http://rhn.redhat.com/errata/RHSA-2015-1187.html
• http://rhn.redhat.com/errata/RHSA-2015-1218.html
• http://rhn.redhat.com/errata/RHSA-2015-1219.html
• http://www.debian.org/security/2015/dsa-3280
• http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
• http://www.securityfocus.com/bid/74700
• http://www.securitytracker.com/id/1032433
• https://bugs.php.net/bug.php?id=69453
• https://security.gentoo.org/glsa/201606-10
• https://support.apple.com/kb/HT205031

Affected products (61)

• cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_hpc_node:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_hpc_node_eus:7.1:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_eus:7.1:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.4.39:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha1:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha2:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha3:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha4:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha5:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:alpha6:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:beta1:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:beta2:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:beta3:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:beta4:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.1:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.2:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.3:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.4:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.5:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.6:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.7:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.8:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.9:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.10:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.11:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.12:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.13:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.14:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.18:*:*:*:*:*:*:*
• cpe:2.3:a:php:php:5.5.19:*:*:*:*:*:*:*

More vulnerabilities in Php

• CVE-2015-0235 — Critical (CVSS 10.0): Heap-based buffer overflow in the __nss_hostname_digits_dots function in glibc 2.2, and other 2.x versions before 2.18,…
• CVE-2012-2688 — Critical (CVSS 10.0): Unspecified vulnerability in the _php_stream_scandir function in the stream implementation in PHP before 5.3.15 and…
• CVE-2012-2376 — Critical (CVSS 10.0): Buffer overflow in the com_print_typeinfo function in PHP 5.4.3 and earlier on Windows allows remote attackers to…
• CVE-2011-3268 — Critical (CVSS 10.0): Buffer overflow in the crypt function in PHP before 5.3.7 allows context-dependent attackers to have an unspecified…
• CVE-2009-4143 — Critical (CVSS 10.0): PHP before 5.2.12 does not properly handle session data, which has unspecified impact and attack vectors related to (1)…
• CVE-2008-5557 — Critical (CVSS 10.0): Heap-based buffer overflow in ext/mbstring/libmbfl/filters/mbfilter_htmlent.c in the mbstring extension in PHP 4.3.0…

All CVEs affecting Php →

Other CWE-189 (Numeric Errors) vulnerabilities

• CVE-2015-8396 — Critical (CVSS 10.0): Integer overflow in the ImageRegionReader::ReadIntoBuffer function in…
• CVE-2015-7205 — Critical (CVSS 10.0): Integer underflow in the RTPReceiverVideo::ParseRtpPacket function in Mozilla Firefox before 43.0 and Firefox ESR 38.x…
• CVE-2015-6575 — Critical (CVSS 10.0): SampleTable.cpp in libstagefright in Android before 5.1.1 LMY48I does not properly consider integer promotion, which…
• CVE-2015-3864 — Critical (CVSS 10.0): Integer underflow in the MPEG4Extractor::parseChunk function in MPEG4Extractor.cpp in libstagefright in mediaserver in…
• CVE-2015-3836 — Critical (CVSS 10.0): The Parse_wave function in arm-wt-22k/lib_src/eas_mdls.c in the Sonivox DLS-to-EAS converter in Android before 5.1.1…
• CVE-2015-3834 — Critical (CVSS 10.0): Multiple integer overflows in the BnHDCP::onTransact function in media/libmedia/IHDCP.cpp in libstagefright in Android…

Browse all CWE-189 (Numeric Errors) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

• 45.84.120.3 (ipv4-addr)
• 221.161.235.168 (ipv4-addr)
• 200.196.50.91 (ipv4-addr)
• 187.141.71.166 (ipv4-addr)
• 187.110.238.50 (ipv4-addr)
• 113.164.66.10 (ipv4-addr)
• 103.38.219.22 (ipv4-addr)
• 103.20.122.54 (ipv4-addr)