phpSysInfo has an IP allowlist (PSI_ALLOWED) bypass via spoofed X-Forwarded-For / Client-IP headers — GHSA-786W-P5PM-CVGH

Summary

## Summary phpSysInfo's `PSI_ALLOWED` IP allowlist can be trivially bypassed by any unauthenticated remote attacker. The access-control check in `read_config.php` derives the client IP from the attacker-controlled `X-Forwarded-For` and `Client-IP` HTTP headers **before** falling back to `REMOTE_ADDR`. An attacker can send `X-Forwarded-For: <an allowed IP>` to impersonate a trusted address and gain full access to…

Timeline

Published by source

2026-08-28

Risk context

• Reported severity or threat level: high.
• Reported CVSS score: 7.5 out of 10.
• Review exposure for the affected product or family: composer: phpsysinfo/phpsysinfo.

Product

composer: phpsysinfo/phpsysinfo

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

Evidence and provenance

Canonical advisory ID

GHSA-786W-P5PM-CVGH

Source

GitHub

Vendor

GitHub

Published by source

2026-08-28

Last source activity

2026-08-28

Additional identifiers

CVE-2026-55584

Curated by

hlukh.ch

Related advisories and connections

These advisories are connected by shared CVE, product, vendor, source, or time signals.