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Age in Days
CVSS Score
Patch within next
Risk Level



30 Days



This vulnerability is 3 years 4 months and 11 days old there are exploits publicly available for it. The vulnerability itself is over a year old, and with there being exploits publicly available it is highly advisable that this vulnerability is patched immediately.



The remote web server uses a version of PHP that is affected by multiple vulnerabilities.


Vulnerability Description

According to its banner, the version of PHP running on the remote web server is 5.4.x prior to 5.4.45. It is, therefore, affected by the following vulnerabilities:

  • Multiple use-after-free memory errors exist related to the unserialize() function. A remote attacker can exploit these errors to execute arbitrary code. (CVE-2015-6834)
  • A use-after-free memory error exists related to the php_var_unserialize() function. A remote attacker, using a crafted serialize string, can exploit this to execute arbitrary code. (CVE-2015-6835)
  • A type confusion error exists related to the serialize_function_call() function due to improper validation of the headers field. A remote attacker can exploit this to have an unspecified impact. (CVE-2015-6836)
  • Multiple flaws exist in the XSLTProcessor class due to improper validation of input from the libxslt library. A remote attacker can exploit these flaws to have an unspecified impact. (CVE-2015-6837, CVE-2015-6838)
  • A flaw exists in the php_zip_extract_file() function in file php_zip.c due to improper sanitization of user-supplied input. An unauthenticated, remote attacker can exploit this to create arbitrary directories outside of the restricted path. (VulnDB 127122)



Upgrade to PHP version 5.4.45 or later.


Further Information



CVE References

CVE-2015-6834 NIST | MITRE | CVEDetails
CVE-2015-6835 NIST | MITRE | CVEDetails
CVE-2015-6836 NIST | MITRE | CVEDetails
CVE-2015-6837 NIST | MITRE | CVEDetails
CVE-2015-6838 NIST | MITRE | CVEDetails


Get in touch

Should you have any questions regarding this or any security matter, please do not hesitate to get in touch by emailing the Hedgehog Cyber Operations Team.

Whilst every effort is made to ensure the accuracy and robustness of any information presented, it is not possible for Hedgehog Cyber to test every possible scenario an organisation may face, and Hedgehog Cyber cannot be held liable for any loss or damage which may arise from taking action on any of the contents provided. Hedgehog Cyber strongly advises that all recommendations, solutions and detection methods detailed, are thoroughly reviewed and tested in non-production environments before being considered suitable for production release, in-line with any existing internal change control procedures.