CRITICAL · 9.8

CVE-2017-8923

The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial ...

Vulnerability Description

The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact by leveraging a script's use of .= with a long string.

CVSS Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH

Affected Products

VendorProductVersions
PhpPhp< 7.4.24

Related Weaknesses (CWE)

References

FAQ

What is CVE-2017-8923?

CVE-2017-8923 is a vulnerability with a CVSS score of 9.8 (CRITICAL). The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial ...

How severe is CVE-2017-8923?

CVE-2017-8923 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2017-8923?

Check the references section above for vendor advisories and patch information. Affected products include: Php Php.