CVE-2026-55584: phpSysInfo has an IP allowlist (PSI_ALLOWED) bypass via spoofed X-Forwarded-For / Client-IP headers

high Affects phpsysinfo/phpsysinfo. Feed 2026.10.29.1, updated 2026-10-28; published 2026-08-28.

phpSysInfo has an IP allowlist (PSI_ALLOWED) bypass via spoofed X-Forwarded-For / Client-IP headers

Package: phpsysinfo/phpsysinfo Composer
Affected versions: <3.4.6
Fixed in: 3.4.6
Severity: high CVSS 7.5
Exploitation: not on CISA KEV · EPSS 2% (79.7th percentile)
Published: 2026-08-28
Source: osv.dev

References

NVD record phpsysinfo/phpsysinfo advisories

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