CVE-2026-55501 | 9router: Login brute-force protection bypass via spoofed X-Forwarded-For header

9Router is an AI router & token saver. Prior to 0.4.80, the dashboard login rate limiter in src/lib/auth/loginLimiter.js derives the client identity from the attacker-controlled X-Forwarded-For HTTP header, and src/app/api/auth/login/route.js uses that spoofable value for checkLock and recordFail. A remote attacker can rotate the X-Forwarded-For value on each login attempt to receive a fresh rate-limit bucket, bypass the 5-attempt threshold and progressive lockout durations, and perform unlimited brute-force attempts against the dashboard password. This issue is fixed in version 0.4.80.

Published: 2026-07-10 Last update: 2026-07-10 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-55501 is rated Moderate Risk (43.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.52%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-55501

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-11 0.52%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-55501

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.3 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.9 3.4 [email protected]

Weakness enumeration for CVE-2026-55501

GitHub Security Advisory for CVE-2026-55501

GHSA-7cfm-pqrj-xgq7 · Severity: high · Ecosystem: npm — 9router: Login brute-force protection bypass via spoofed X-Forwarded-For header

Affected software / configurations for CVE-2026-55501

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-55501

cvelogic Threat Intelligence