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 of service (application crash) or possibly have unspecified other impact by leveraging a script's use of .= with a long string.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugs.php.net/bug.php?id=74577	Exploit Issue Tracking Vendor Advisory
http://www.securityfocus.com/bid/98518	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:php:php::::::::
	cpe:2.3:a:php:php::::::::

Information

Published : 2017-05-12 13:29

Updated : 2022-07-20 09:32

NVD link : CVE-2017-8923

Mitre link : CVE-2017-8923

JSON object : View

CWE

CWE-787

Out-of-bounds Write

Products Affected

php

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9.8 /10