Critical severity · published May 12, 2017
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…
9.8
CVSS
7.2%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)7.2% · higher than 94% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PH
PHP · PHP
before 7.4.24; 8.0.0 before 8.0.11 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2017-8923
CVE.org
https://www.cve.org/CVERecord?id=CVE-2017-8923
Third Party Advisory
http://www.securityfocus.com/bid/98518
Exploit
https://bugs.php.net/bug.php?id=74577
security.netapp.com
https://security.netapp.com/advisory/ntap-20241227-0007/
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