CVE-2026-78168: ipTIME T24000M Auth Bypass Vulnerability

CVE-2026-78168 Overview

CVE-2026-78168 is an improper authentication vulnerability [CWE-287] affecting EFM ipTIME T24000M routers through firmware version 14.20.0. The flaw resides in the httpcon_check_session_url function within the Session Validation Handler component. Attackers can manipulate session validation logic remotely without authentication or user interaction. Public disclosure of the exploit technique has occurred, and the vendor did not respond to early disclosure attempts.

Critical Impact
Remote attackers can bypass session validation on affected ipTIME T24000M devices, gaining unauthorized access to router administrative functions with high impact to confidentiality, integrity, and availability.

Affected Products

EFM ipTIME T24000M firmware up to and including version 14.20.0
Component: Session Validation Handler (httpcon_check_session_url function)
Deployments exposing the router web management interface to untrusted networks

Discovery Timeline

2026-08-24 - CVE-2026-78168 published to NVD
2026-08-27 - Last updated in NVD database

Technical Details for CVE-2026-78168

Vulnerability Analysis

The vulnerability is an improper authentication weakness in the httpcon_check_session_url function, which is responsible for validating HTTP session state before granting access to protected router URLs. Manipulation of the request parameters processed by this function causes the session check to return a valid state for unauthenticated requests. The result is an authentication bypass reachable directly over the network.

Because session validation is the primary gate protecting the administrative web interface, a successful bypass exposes configuration endpoints intended for authenticated administrators. An attacker leveraging this weakness can read device configuration, alter routing and firewall rules, and disrupt network availability. The flaw requires no privileges, no user interaction, and low attack complexity.

Root Cause

The root cause is flawed logic in httpcon_check_session_url that fails to correctly enforce authenticated session state for protected URLs. Session validation appears to rely on attacker-controllable request attributes rather than a server-side authenticated session binding. This maps directly to [CWE-287: Improper Authentication].

Attack Vector

Exploitation occurs remotely over the network by sending crafted HTTP requests to the router management interface. No credentials, tokens, or prior foothold are required. Devices exposing the web administration service to the internet or to untrusted network segments are directly reachable. Public disclosure of the technique increases the likelihood of automated scanning and mass exploitation attempts.

No verified public proof-of-concept code is available for reproduction in this article. Refer to the GitHub CVE Issue #10 and VulDB entry for CVE-2026-78168 for additional technical context.

Detection Methods for CVE-2026-78168

Indicators of Compromise

Unauthenticated HTTP requests to router administration URLs returning 200 OK responses instead of authentication challenges
New or modified administrative accounts, DNS server entries, or port-forwarding rules on ipTIME T24000M devices
Outbound connections from the router to unfamiliar hosts, indicating post-exploitation configuration changes
Unexpected reboots or configuration resets logged by the device

Detection Strategies

Inspect web server access logs on affected devices for repeated requests to session-protected paths lacking valid session cookies or tokens
Deploy network intrusion detection signatures that flag HTTP requests targeting ipTIME administrative endpoints from external sources
Baseline router configuration state and alert on unauthorized changes to WAN, DNS, or firewall rules

Monitoring Recommendations

Forward router syslog and administrative event logs to a centralized SIEM or data lake for continuous correlation
Monitor for anomalous administrative logins outside expected source IP ranges and business hours
Track firmware version inventory across all ipTIME T24000M devices to identify unpatched units

How to Mitigate CVE-2026-78168

Immediate Actions Required

Restrict access to the router web management interface to trusted internal networks only and disable remote WAN administration
Place ipTIME T24000M devices behind a network segmentation boundary that blocks untrusted inbound HTTP and HTTPS traffic
Rotate all administrative credentials and review device configuration for unauthorized changes
Inventory affected devices running firmware 14.20.0 or earlier and prioritize replacement or isolation

Patch Information

No vendor patch has been published at the time of NVD publication. According to the CVE record, the vendor did not respond to disclosure outreach. Monitor the EFM ipTIME vendor site and the VulDB vulnerability record for firmware updates. Consider replacing affected devices if a supported firmware release is not made available.

Workarounds

Disable remote management on the WAN interface and permit administrative access only from a dedicated management VLAN
Enforce access control lists on upstream firewalls that block inbound TCP to router management ports from untrusted sources
Require VPN connectivity for any remote administration of the affected routers
Deploy a reverse proxy or web application firewall in front of the management interface where feasible, filtering unauthenticated requests to protected URLs

bash

# Example upstream firewall rule to block inbound access to router admin ports
# Adjust interface names and management port to match your environment
iptables -A FORWARD -i wan0 -p tcp --dport 80 -d <router_ip> -j DROP
iptables -A FORWARD -i wan0 -p tcp --dport 443 -d <router_ip> -j DROP