Is CVE-2012-4388 being actively exploited?

CVE-2012-4388 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2012-4388?

CVE-2012-4388 has a CVSS 2.0 base score of 4.3 (MEDIUM).

CVE-2012-4388

MEDIUM · CVSS 4.3EPSS 4.2%EU EUVD

The sapi_header_op function in main/SAPI.c in PHP 5.4.0RC2 through 5.4.0 does not properly determine a pointer during checks for %0D sequences (aka carriage return characters), which allows remote attackers to bypass an HTTP response-splitting protection mechanism via a crafted URL, related to improper interaction between the PHP header function and certain browsers, as demonstrated by Internet Explorer and Google Chrome. NOTE: this vulnerability exists because of an incorrect fix for CVE-2011-1398.

Key facts

CVSS score: 4.3 (v2.0)
Severity: MEDIUM
CVSS vector: AV:N/AC:M/Au:N/C:N/I:P/A:N
Weakness (CWE): CWE-20
EPSS score: 4.2% (91th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2012-4328)
Published: September 7, 2012
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2012-4328 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.

View on the EU Vulnerability Database

Affected products

canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
debian / debian linux
php / php
php / php

References

http://article.gmane.org/gmane.comp.php.devel/70584(Broken Link)
http://lists.opensuse.org/opensuse-security-announce/2013-08/msg00006.html(Mailing List, Third Party Advisory)
http://openwall.com/lists/oss-security/2012/08/29/5(Mailing List, Third Party Advisory)
http://openwall.com/lists/oss-security/2012/09/02/1(Mailing List, Third Party Advisory)
http://openwall.com/lists/oss-security/2012/09/05/15(Mailing List, Third Party Advisory)
http://openwall.com/lists/oss-security/2012/09/07/3(Mailing List, Third Party Advisory)
http://security-tracker.debian.org/tracker/CVE-2012-4388(Third Party Advisory)
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_4/main/SAPI.c?r1=323986&r2=323985&pathrev=323986(Exploit, Patch, Vendor Advisory)
http://www.securitytracker.com/id?1027463(Third Party Advisory, VDB Entry)
http://www.ubuntu.com/usn/USN-1569-1(Third Party Advisory)
https://bugs.php.net/bug.php?id=60227(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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