CVE-2017-7189

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-07-10 · updated 2026-06-17
Weakness: CWE-20

Description

main/streams/xp_socket.c in PHP 7.x before 2017-03-07 misparses fsockopen calls, such as by interpreting fsockopen('127.0.0.1:80', 443) as if the address/port were 127.0.0.1:80:443, which is later truncated to 127.0.0.1:80. This behavior has a security risk if the explicitly provided port number (i.e., 443 in this example) is hardcoded into an application as a security policy, but the hostname argument (i.e., 127.0.0.1:80 in this example) is obtained from untrusted input.

Affected products

PHP: from 7.0.0 before 7.0.16 — fixed in 7.0.16

How to fix

Upgrade to a fixed version: PHP 7.0.16. Check the vendor advisory for mitigations.

References

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