← Vulnerability feed

Vulnerability record · CVE-2017-8923 · published 12 May 2017

CVE-2017-8923: Php out-of-bounds write vulnerability

Php · Php

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.

9.8 CVSS 3.1 Critical EPSS 7.2% · top 5.9% CWE-787 · Out-of-bounds write
9.8CVSS 3.1 base score, v2 7.5
7.2%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
5References, 2 tagged exploit
17 Jun 2026Last modified by NVD

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://www.securityfocus.com/bid/98518 Third Party AdvisoryVDB Entry
https://bugs.php.net/bug.php?id=74577 ExploitIssue TrackingVendor Advisory
http://www.securityfocus.com/bid/98518 Third Party AdvisoryVDB Entry
https://bugs.php.net/bug.php?id=74577 ExploitIssue TrackingVendor Advisory
https://security.netapp.com/advisory/ntap-20241227-0007/

Track CVE-2017-8923 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2024-4577PHP-CGI on Windows argument injection leads to remote code executionPHP-CGI on Windows can misinterpret characters in the command line passed to Win32 API functions when certain code pages are configured, due to Windo…KEVEPSS 100%analysed9.8CVE-2019-11043PHP-FPM buffer overflow enables remote code executionPHP-FPM in certain configurations writes past allocated buffers into FCGI protocol data space, an out-of-bounds write (CWE-787, CWE-120). It affects …KEVEPSS 100%analysed9.8CVE-2012-1823PHP-CGI query string option injection enables remote code executionPHP versions before 5.3.12 and 5.4.x before 5.4.2, when run as a CGI script (php-cgi), mishandle query strings that lack an equals sign, allowing com…KEVEPSS 100%analysed10.0CVE-2015-0235glibc gethostbyname heap buffer overflow (GHOST)CVE-2015-0235 is a heap-based buffer overflow in the __nss_hostname_digits_dots function in glibc 2.2 and other 2.x versions before 2.18. It is reach…EPSS 95%analysed10.0CVE-2012-2688Php vulnerabilityUnspecified vulnerability in the _php_stream_scandir function in the stream implementation in PHP before 5.3.15 and 5.4.x before 5.4.5 has unknown im…EPSS 10%10.0CVE-2012-2376Php memory buffer overflow vulnerabilityBuffer overflow in the com_print_typeinfo function in PHP 5.4.3 and earlier on Windows allows remote attackers to execute arbitrary code via crafted …EPSS 20%10.0CVE-2011-3268Php memory buffer overflow vulnerabilityBuffer overflow in the crypt function in PHP before 5.3.7 allows context-dependent attackers to have an unspecified impact via a long salt argument, …EPSS 5.7%10.0CVE-2009-4143Php vulnerabilityPHP before 5.2.12 does not properly handle session data, which has unspecified impact and attack vectors related to (1) interrupt corruption of the S…EPSS 2.9%

Source: NIST National Vulnerability Database (record CVE-2017-8923), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.