CVE-2017-8923

Public Exploit

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 5.27% Top 15%
Vendor Advisory php.net
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://www.securityfocus.com/bid/98518 vdb entry third party advisory
https://bugs.php.net/bug.php?id=74577 issue tracking exploit vendor advisory
https://security.netapp.com/advisory/ntap-20241227-0007/

Frequently Asked Questions

What is the severity of CVE-2017-8923?
CVE-2017-8923 has been scored as a critical severity vulnerability.
How to fix CVE-2017-8923?
To fix CVE-2017-8923, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2017-8923 being actively exploited in the wild?
It is possible that CVE-2017-8923 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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