CVE-2026-1758

Executive Summary

CVE-2026-1758 is a session fixation vulnerability in the webserver module of Secomea GateManager, affecting versions 11.5 and 11.4.625515072. An unauthenticated, remote attacker can leverage this flaw to fixate a victim's session identifier and subsequently hijack that authenticated session, potentially gaining full control over the industrial remote-access gateway. The vulnerability carries a CVSS score of 8.3 (High), has no known public proof-of-concept, and is not listed in CISA KEV; patches exist in GateManager 11.6 or 11.4.626194074 and above, but patch-source tracking yields a confidence of 0/4, indicating no confirmed patch evidence from the tracked feeds.

Technical Analysis

The vulnerability is classified as CWE-384: Session Fixation. It resides in the webserver module of Secomea GateManager. Session fixation occurs when a web application fails to invalidate or regenerate a pre-authentication session identifier after a user successfully authenticates. An attacker who can set or predict a victim's session ID — typically by forcing the victim to use an attacker-supplied session token — can then reuse that same session ID after the victim logs in, effectively assuming the victim's authenticated session.

The NVD description states: "Session fixation vulnerability in Secomea GateManager (webserver module) allows Session Fixation." It further specifies: "This issue affects GateManager: 11.5;0, 11.4.625515072:0. Fixed in Version 11.6 or 11.4.626194074 and above."

The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L indicates:

• Attack Vector: Network (AV:N) — exploitable remotely over the network.
• Attack Complexity: Low (AC:L) — no specialized conditions required.
• Privileges Required: None (PR:N) — no authentication needed to initiate the attack.
• User Interaction: Required (UI:R) — the victim must interact (e.g., click a crafted link, submit a form) for the attack to succeed.
• Scope: Unchanged (S:U) — the impact remains within the vulnerable component.
• Confidentiality: High (C:H), Integrity: High (I:H), Availability: Low (A:L).

The exact implementation detail of how the session ID is fixed (e.g., via URL parameter, cookie injection, or form pre-population) is not disclosed in the available data. No specific function names, endpoints, or parameter names are provided in the NVD description. The attack surface is the GateManager web interface, which is typically exposed to the internet to provide remote access to industrial control systems (ICS) and OT networks.

Exploitation Scenarios

No public PoC is available; the attack chain below is inferred from the session fixation vulnerability class and the CVSS vector.

1. Reconnaissance/Target Identification: The attacker identifies an internet-facing Secomea GateManager instance by scanning for the web interface (e.g., using Shodan dorks like product:"Secomea GateManager" or http.title:"GateManager"). The attacker verifies the version is 11.5 or 11.4.625515072 by inspecting the login page or any version-disclosing response headers.

2. Triggering the Flaw: The attacker crafts a link or form submission that causes the victim's browser to use a session identifier chosen by the attacker. This is the classic session fixation pattern: the attacker first obtains a valid session ID from the GateManager webserver (e.g., by visiting the login page themselves), then tricks the victim into using that same session ID. The method of forcing the session ID (e.g., via URL parameter, cookie injection, or a crafted POST) is not specified in the available data. The attacker must induce the victim to interact (UI:R), such as by clicking a link in a phishing email.

3. Authentication Hijack: The victim clicks the crafted link and logs into GateManager using their legitimate credentials. Because the application fails to regenerate the session ID after authentication, the session ID remains the one known to the attacker. The attacker, who already knows the session ID, can now access the victim's authenticated session.

4. Post-Exploitation Impact: With the hijacked session, the attacker gains the victim's privileges within GateManager. Depending on the victim's role (e.g., administrator), the attacker could view sensitive configuration data, modify settings, pivot to connected industrial networks, or disrupt remote access for operational technology (OT) systems. The CVSS score reflects High confidentiality and integrity impact and Low availability impact. No public exploit code exists, and exploitation is not known to be occurring in the wild.

Impact Assessment

Secomea GateManager is a remote access gateway widely used in industrial and OT environments to enable secure connectivity to PLCs, HMIs, and other control system devices. A successful session fixation attack could allow an attacker to hijack an authenticated administrator session and then:

• Access sensitive configuration and network topology information (High confidentiality impact).
• Modify gateway settings, user accounts, or firewall rules (High integrity impact).
• Potentially cause limited disruption (Low availability impact), such as disconnecting remote sessions. The blast radius extends to any industrial network reachable through the compromised gateway. Because GateManager often acts as a critical access point, compromise could lead to lateral movement into OT networks, impacting physical processes. The CVSS score of 8.3 (High) aligns with these risks. However, exploitation requires user interaction, and no public exploit is available, somewhat limiting immediate risk. The lack of patch evidence from tracked sources (confidence 0/4) means many organizations may remain unpatched, increasing exposure.

Detection Guidance

Sigma Rule

title: Secomea GateManager Session Fixation Attempt
id: 8f7c3a2e-1b4d-4e6f-9a8b-7c6d5e4f3a2b
status: experimental
description: Detects potential session fixation attempts against Secomea GateManager webserver by monitoring for repeated logins with the same session identifier.
author: Threat Intelligence Team
date: 2026-07-15
logsource:
  category: webserver
  product: secomea_gatemanager
detection:
  selection_login:
    cs-method: 'POST'
    cs-uri-path: '/login'
    sc-status: 200
  selection_session:
    cs-cookie|contains: 'JSESSIONID'
  condition: selection_login and selection_session
fields:
  - c-ip
  - cs-uri
  - cs-cookie
falsepositives:
  - Legitimate users with long-lived sessions
level: medium
tags:
  - attack.t1190
  - cve.2026.1758

YARA Rule

rule CVE_2026_1758_Secomea_GateManager_SessionFixation
{
    meta:
        description = "Detects session fixation indicators in Secomea GateManager webserver responses"
        author = "Threat Intelligence Team"
        date = "2026-07-15"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-1758"
        cve = "CVE-2026-1758"
    strings:
        $session_cookie = "JSESSIONID" ascii wide nocase
        $gatemanager = "GateManager" ascii wide nocase
        $version_11_5 = "11.5" ascii wide
        $version_11_4 = "11.4.625515072" ascii wide
    condition:
        ($gatemanager or $version_11_5 or $version_11_4) and $session_cookie
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-1758 Secomea GateManager Session Fixation Attempt"; flow:to_server,established; http.method; content:"POST"; http.uri; content:"/login"; http.cookie; content:"JSESSIONID"; reference:cve,2026-1758; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-1758; classtype:attempted-user; sid:10000001; rev:1;)

Elastic Detection

sequence by source.ip with maxspan=5m
  [ network where network.protocol == "http" and http.request.method == "POST" and url.path == "/login" and http.response.status_code == 200 ]
  [ network where network.protocol == "http" and http.request.method == "GET" and http.request.headers.cookie : "*JSESSIONID*" and source.ip == destination.ip ]

Splunk SPL Query

index=web sourcetype=access_combined
| search method=POST uri_path="/login" status=200
| rex field=cookie "JSESSIONID=(?<session_id>[^;]+)"
| stats count values(session_id) as sessions by src_ip
| where count > 5 AND mvcount(sessions) == 1
| table src_ip, count, sessions

Wazuh OSSEC Rule

<group name="web,secomea_gatemanager,">
  <rule id="100001" level="10">
    <decoded_as>web-accesslog</decoded_as>
    <field name="url">/login</field>
    <field name="method">POST</field>
    <regex field="id">JSESSIONID</regex>
    <description>CVE-2026-1758: Potential Secomea GateManager session fixation attempt - repeated login with same session ID</description>
    <mitre>
      <id>T1190</id>
    </mitre>
    <group>cve_2026_1758,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source).

1. Immediate Mitigations:

   • Restrict network access to the GateManager web interface to trusted IP ranges using firewalls or VPNs.
   • Enable multi-factor authentication (MFA) if supported, which can limit the impact of session hijacking.
   • Educate users about phishing and social engineering, as the attack requires user interaction.
   • Monitor web logs for anomalous session behavior, such as multiple logins from different IPs using the same session ID.

2. Patch/Upgrade Steps:

   • Upgrade to GateManager version 11.6 or 11.4.626194074 and above. The NVD description states these versions fix the issue.
   • Verify the upgrade by checking the version number in the GateManager interface or via the vendor's official verification method.
   • If upgrade is not immediately possible, apply vendor-recommended workarounds if available (none specified in the data).

3. Long-Term Hardening:

   • Ensure the web application regenerates session identifiers upon successful authentication, a standard secure coding practice.
   • Regularly review and update remote access gateways, especially those exposed to the internet.
   • Implement network segmentation to limit the blast radius if a gateway is compromised.
   • Conduct periodic vulnerability scans and penetration tests on OT/ICS infrastructure.
   • Subscribe to Secomea security advisories and monitor CVE feeds for updates.

References

1. NVD – CVE-2026-1758: https://nvd.nist.gov/vuln/detail/CVE-2026-1758
2. Secomea GateManager Security Advisory (vendor advisory – check Secomea website for official notice)
3. CWE-384: Session Fixation – https://cwe.mitre.org/data/definitions/384.html
4. CISA Known Exploited Vulnerabilities Catalog (not listed as of report date) – https://www.cisa.gov/known-exploited-vulnerabilities-catalog
5. OWASP Session Fixation – https://owasp.org/www-community/attacks/Session_fixation No known threat actor campaigns or exploit-in-the-wild evidence available at this time.