CVE-2021-4226

RSFirewall < 1.1.25 - IP Block Bypass

Critical · published December 15, 2022

CVSS v3.1
9.8
EPSS
1%
Percentile
45.0
In the wild
Unconfirmed
What it is

🚨 A crafty IP address bypass is hiding in RSFirewall's HTTP header checks! One exploit can make it think it's a different user — talk about an identity crisis! 🔥 Think of RSFirewall as a bouncer at a club who checks IDs by looking at multiple sources of information. If that bouncer gets tricked by a fake ID because of a loophole in the checking process, then anyone can waltz in under a false identity! This vulnerability allows an attacker to impersonate any user by manipulating HTTP headers, potentially gaining unauthorized access to sensitive data or functionalities. With a CVSS score of 9.8, this could lead to complete account takeover, leaving your site wide open to malicious activities and data breaches — absolutely devastating!

Put simply

Think of RSFirewall as a bouncer at a club who checks IDs by looking at multiple sources of information. If that bouncer gets tricked by a fake ID because of a loophole in the checking process, then anyone can waltz in under a false identity! This vulnerability arises because RSFirewall inadequately verifies the original IP address from HTTP headers, allowing an attacker to bypass checks by spoofing their identity — a serious oversight that compromises security!

What to do

This vulnerability allows an attacker to impersonate any user by manipulating HTTP headers, potentially gaining unauthorized access to sensitive data or functionalities. With a CVSS score of 9.8, this could lead to complete account takeover, leaving your site wide open to malicious activities and data breaches — absolutely devastating! Immediately patch RSFirewall to the latest version to close this loophole. Review and strengthen your HTTP header validation processes to ensure only legitimate addresses are accepted. It's crucial to audit all access logs for any suspicious activity while you're at it! You've got this! Follow these steps and you'll ensure RSFirewall is locked down tighter than ever! 🛡️

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00546 · 45.0th percentile
Published
2022-12-15T17:14Z
EPSS history
Timeline
  • 15 DEC 17:14Z
    RSFirewall < 1.1.25 - IP Block Bypass
    cvelistv5