CVE-2026-55584
High
Description
phpSysInfo is a customizable PHP script that displays system information. Prior to 3.4.6, the PSI_ALLOWED access-control check in read_config.php trusts attacker-controlled X-Forwarded-For and Client-IP HTTP headers before REMOTE_ADDR. A remote unauthenticated attacker can supply an allowed address in one of these headers to impersonate a trusted client and access exposed hostname, kernel, CPU, memory, filesystem, and network-interface information. This issue is fixed in version 3.4.6.
SeverityHigh
CVSS7.5
Exploit probability—
ProductPhpsysinfo/phpsysinfo
PublishedAug 28, 2026
First seenAug 28, 2026
Weakness typeCWE-290CWE-290
How to fix
Update
- phpsysinfo/phpsysinfo3.4.6 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| phpsysinfo/phpsysinfoPackagist | v < 3.4.6 | 3.4.6 |
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