CVE-2026-12622: GridTime 3000 Open Redirect Vulnerability

CVE-2026-12622 Overview

CVE-2026-12622 is an open redirect vulnerability [CWE-601] affecting the Microchip GridTime 3000 GNSS Time Server. The flaw resides in the password change form submission, where the application fails to validate redirect destinations supplied through user-controlled input. Authenticated attackers can craft URLs that redirect victims to attacker-controlled domains after interacting with the password change workflow. Affected firmware versions span from 1.0r0.03 through 1.1r0.0. The vulnerability is exploitable over the network and requires low privileges with no user interaction beyond following the manipulated link.

Critical Impact
Attackers can leverage the trusted GridTime 3000 management interface to redirect users to phishing pages, harvest credentials, or stage follow-on attacks against operators of critical timing infrastructure.

Affected Products

Microchip GridTime 3000 GNSS Time Server firmware 1.0r0.03
Microchip GridTime 3000 GNSS Time Server firmware versions between 1.0r0.03 and 1.1r0.0
Microchip GridTime 3000 GNSS Time Server firmware 1.1r0.0

Discovery Timeline

2026-06-19 - CVE-2026-12622 published to NVD
2026-06-22 - Last updated in NVD database

Technical Details for CVE-2026-12622

Vulnerability Analysis

The GridTime 3000 GNSS Time Server exposes a web management interface for administrative tasks, including password changes. The password change form submission accepts a redirect parameter that is not validated against an allowlist of trusted destinations. An authenticated attacker can supply an external URL as the redirect target. When a victim submits the form or follows a crafted link, the application issues an HTTP redirect to the attacker-controlled domain.

Open redirect flaws in network infrastructure devices carry elevated risk because operators trust the device's management URL. The GridTime 3000 serves timing data to critical operational environments, so phishing attacks launched from its interface can be highly effective against engineering and administrative staff.

Root Cause

The root cause is missing or insufficient validation of redirect destinations in the password change handler. The application trusts user-supplied input for the post-submission redirect target without enforcing same-origin checks, allowlists, or relative-path constraints. This pattern aligns with CWE-601: URL Redirection to Untrusted Site.

Attack Vector

Exploitation requires network access to the GridTime 3000 management interface and low-privileged authenticated access. The attacker crafts a URL pointing to the password change endpoint with a malicious redirect parameter. The attacker then distributes this URL to operators through email, chat, or other channels. When the victim interacts with the link inside an authenticated session, the device returns an HTTP redirect to the attacker's domain, which can host a cloned login portal or malware delivery page.

The vulnerability is described in prose because no public proof-of-concept exists. Refer to the Microchip Security Vulnerability Reporting page for vendor technical details.

Detection Methods for CVE-2026-12622

Indicators of Compromise

HTTP 302 or 303 responses from the GridTime 3000 password change endpoint pointing to external domains
Inbound requests to the password change form containing redirect parameters with absolute URLs or protocol-relative paths
Web proxy logs showing operator browsers transitioning from the GridTime management host to unknown external domains immediately after a password change request

Detection Strategies

Inspect GridTime 3000 web server access logs for password change requests containing URL-encoded redirect parameters referencing external hosts
Monitor egress traffic from operator workstations for sessions that originate from the GridTime management interface and pivot to newly registered or low-reputation domains
Deploy network intrusion detection signatures that flag HTTP redirects from known GridTime management IPs to non-allowlisted destinations

Monitoring Recommendations

Centralize GridTime 3000 web logs in a SIEM and alert on anomalous redirect patterns associated with the password change endpoint
Correlate authentication events on the GridTime appliance with downstream phishing indicators in email and identity logs
Track URL reputation for any domain referenced in redirect parameters and block known malicious destinations at the perimeter

How to Mitigate CVE-2026-12622

Immediate Actions Required

Restrict network access to the GridTime 3000 management interface using firewall rules and management VLAN segmentation
Require operators to access the management interface only through bookmarked URLs, not links received via email or messaging
Audit recent password change activity on affected appliances and confirm operator-initiated requests

Patch Information

Microchip has published vulnerability information on the GridTime 3000 GNSS Time Server open redirect advisory page. Operators should contact Microchip support to obtain firmware releases that address the open redirect in versions between 1.0r0.03 and 1.1r0.0 and apply the update during the next maintenance window.

Workarounds

Place the GridTime 3000 management interface behind a reverse proxy that strips or validates redirect parameters before forwarding requests
Enforce strict referrer and origin checks at the network perimeter for traffic destined to the password change endpoint
Train operators to verify the browser address bar after submitting credential changes and to report unexpected domain transitions

bash

# Example reverse proxy rule to drop external redirect parameters
# (nginx) - block requests with absolute URLs in redirect query strings
if ($args ~* "redirect=https?:\/\/") {
    return 403;
}