CVE-2026-55584CWE-290

CVE-2026-55584

High · published August 29, 2026

CVSS v3.1
7.5
EPSS
2%
Percentile
79.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.01910 · 79.6th percentile
Weakness
CWE-290 · Authentication Bypass by Spoofing
Published
2026-08-29T00:18Z
References (3)
EPSS history
Timeline
  • 30 AUG 16:18Z
    EPSS moved — → 2%
    epss
  • 28 AUG 18:29Z
    phpSysInfo: IP allowlist (PSI_ALLOWED) bypass via spoofed X-Forwarded-For / Client-IP headers
    cvelistv5