CVE-2026-109526

Executive Summary

CVE-2026-109526 is a locally exploitable information disclosure vulnerability in HBAI-Ltd's Toonflow-app, affecting versions up to and including 1.1.8. The flaw resides in the exportData endpoint component and allows an attacker with local access and low privileges to read data they should not have access to, with a disclosed public exploit. According to the vendor, the vulnerable code paths no longer exist in the current release (2.0.4), which resulted from a substantial architectural refactor, and the issue is not present in any supported release.

Technical Analysis

The vulnerability is classified as CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). Per the NVD description, the affected component is an unknown function of the exportData Endpoint within Toonflow-app up to version 1.1.8. Manipulation of this endpoint leads to information disclosure. No specific function names, parameter names, file paths, or API internals are provided in the available description or CNA title, so the analysis must remain at the vulnerability-class level.

Key technical characteristics derivable from the provided data:

• Attack Vector (AV:L): The attack must be approached locally. This means the attacker requires either interactive access to the host or the ability to execute code locally in the context of an authenticated user. This substantially narrows the threat model — remote unauthenticated exploitation is not implied by the vector.
• Privileges Required (PR:L): Low privileges are sufficient. The attacker does not need administrative rights; a standard user session that can reach the exportData endpoint is enough.
• User Interaction (UI:N): No victim action is needed beyond the attacker's own local execution.
• Scope (S:U): The impact is confined to the vulnerable component; no privilege boundary crossing outside the security authority is scored.
• Confidentiality (C:L): Limited confidentiality impact — the exposed data is bounded, not a full system compromise.
• Integrity (I:N) / Availability (A:N): No integrity or availability impact; this is a pure read/exposure issue.

The mechanism class is an access-control or output-sanitization weakness in the exportData endpoint: an exported data set is generated and returned without adequate authorization or filtering, exposing sensitive content to a local low-privileged caller. Because the description does not specify whether the root cause is missing authorization checks, improper filtering of exported fields, or insufficient scoping of the export query, those specifics must not be assumed. What can be stated is that the exportData functionality fails to enforce an appropriate access boundary on the information it returns.

The vendor's position is important: they state the report targets version 1.1.8, that the current release is 2.0.4, and that the referenced code paths do not apply to the current version. This is effectively a refactor-as-remediation outcome rather than a targeted security patch, which affects how defenders should treat version-based detection.

Exploitation Scenarios

The following attack chain is inferred from the vulnerability class and the NVD description. No public PoC or exploit code is available in the tracked data set; the chain is described at the class level and does not assert specific implementation details.

1. Reconnaissance / target identification. The attacker first determines whether the target host runs Toonflow-app at a vulnerable version (≤ 1.1.8). This can be done locally by inspecting the installed application, its version metadata, or the presence of the exportData endpoint. Because the attack is local (AV:L) and requires low privileges (PR:L), reconnaissance is moot for a remote adversary — the attacker already has a foothold on the host or an interactive session.

2. Triggering the flaw class. With a low-privileged local session, the attacker invokes the exportData endpoint through whatever local interface the application exposes (CLI, local web UI, or IPC). The weakness is an information-disclosure condition: the endpoint returns exported data without properly enforcing access boundaries on that data. The attacker does not need elevated rights; the low-privilege session is sufficient per PR:L.

3. Execution method. At the vulnerability-class level, exploitation is a direct request/trigger against the exportData functionality. No memory corruption, injection primitive, or remote payload is implied by the description. The attacker's "payload" is simply the request that causes the endpoint to emit data the caller should not receive. No specific parameter names or code patterns can be asserted, as none are provided.

4. Post-exploitation impact. The exposed export may contain sensitive content that expands the attacker's knowledge of the environment — for example, configuration or application data included in the export scope. The scored impact is limited confidentiality (C:L) with no integrity or availability effect. In a local multi-user or shared-host scenario, this can facilitate lateral movement or privilege escalation planning, but no such follow-on capability is claimed by the advisory itself.

Important caveat: The vendor disputes the applicability of this report to supported releases, noting the referenced code paths were removed in the 2.0.x refactor. Defenders on 2.0.x should not treat this CVE as actionable based on this advisory alone.

Impact Assessment

The CVSS v3.1 base score is 3.3 (LOW), vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N. Subscore interpretation:

• Exploitability: Local vector with low attack complexity and low privileges — easy to execute if the attacker already has local access. There is no user-interaction barrier and no special conditions beyond local reachability of the endpoint.
• Impact: Only confidentiality is affected, and only at a "Low" level. No data integrity or service availability loss.
• Blast radius: Confined to systems where Toonflow-app ≤ 1.1.8 is installed and where untrusted or lower-privileged local users can reach the application's exportData functionality. The local attack vector and low confidentiality score mean the practical blast radius is narrow — this is not a wormable or internet-exposed mass-exploitation candidate.

Business impact is therefore primarily:

• Unauthorized exposure of data contained in application exports on shared or multi-tenant hosts.
• Potential compliance implications if exported data includes regulated or sensitive records (assessment depends on an organization's data classification; the advisory does not specify what the export contains).
• Low urgency relative to remote, unauthenticated, or high-integrity-impact vulnerabilities, but non-zero for environments hosting untrusted local users.

EPSS: Not yet scored by FIRST.org. No exploit-in-the-wild evidence is available in the provided data, and the CVE is not in CISA KEV. While a public disclosure exists per NVD ("the exploit has been disclosed to the public and may be used"), no PoC or exploit code was confirmed in the tracked sources for this report.

Detection Guidance

Detection of this vulnerability is challenging because the triggering action is a local call to the exportData endpoint, not necessarily a network event. The rules below emphasize process-level, file-level, and host-audit telemetry; the Suricata rule is provided for deployments where the endpoint is reachable over a local HTTP loopback interface and is therefore capturable.

Sigma Rule

title: Potential Toonflow-app exportData Information Disclosure (CVE-2026-109526)
id: 3f9c1a76-2b4d-4e8a-9c11-7a5e2d0b8f31
status: experimental
description: Detects local access to the Toonflow-app exportData endpoint associated with CVE-2026-109526. Requires host telemetry as the attack vector is local.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-109526
author: valtersit.com
date: 2026/01/01
logsource:
  category: process_creation
  product: linux
detection:
  selection_app:
    Image|endswith:
      - '/toonflow'
      - '/toonflow-app'
    CommandLine|contains:
      - 'exportData'
      - 'export_data'
      - 'export-data'
  selection_child:
    ParentImage|endswith:
      - '/toonflow'
      - '/toonflow-app'
    CommandLine|contains:
      - 'exportData'
  condition: selection_app or selection_child
fields:
  - Image
  - CommandLine
  - ParentImage
  - User
falsepositives:
  - Legitimate administrative exports by authorized operators
  - Automated backup jobs invoking the export function
level: low
tags:
  - attack.t1213
  - cve.2026.109526

YARA Rule

rule CVE_2026_109526_Toonflow_exportData_Disclosure
{
    meta:
        description = "Detects references to the Toonflow-app exportData endpoint associated with CVE-2026-109526 in application files or logs"
        author = "valtersit.com"
        date = "2026-01-01"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-109526"
        cve = "CVE-2026-109526"

    strings:
        $s1 = "exportData" ascii wide nocase
        $s2 = "export_data" ascii wide nocase
        $s3 = "Toonflow" ascii wide nocase
        $s4 = "ToonFlow" ascii wide nocase

    condition:
        uint16(0) == 0x5A4D or
        (2 of ($s1, $s2) and any of ($s3, $s4)) or
        (any of ($s1, $s2) and filesize < 5MB)
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-109526 Toonflow-app exportData Information Disclosure Attempt"; flow:to_server,established; http.uri; content:"exportData"; nocase; http.header; content:"Host"; distance:0; classtype:attempted-recon; reference:cve,2026-109526; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-109526; sid:2026109526; rev:1; metadata:created_at 2026_01_01, updated_at 2026_01_01, affected_product Toonflow-app;)

Elastic Detection

process where process.parent.name : ("toonflow", "toonflow-app") and
  process.command_line : "*exportData*"

Splunk SPL Query

index=* (sourcetype=linux_audit OR sourcetype=sysmon OR sourcetype=WinEventLog:Security)
| search (process_path="*toonflow*" OR parent_process_path="*toonflow*")
| search (process="*exportData*" OR command_line="*exportData*" OR command_line="*export_data*")
| stats count min(_time) as first_seen max(_time) as last_seen
        values(user) as users values(process_path) as proc values(command_line) as cmd
        by host
| where count > 0
| convert ctime(first_seen) ctime(last_seen)

Wazuh OSSEC Rule

<group name="toonflow,cve-2026-109526,">
  <rule id="100526" level="5">
    <decoded_as>json</decoded_as>
    <field name="command_line">exportData</field>
    <description>CVE-2026-109526: Possible Toonflow-app exportData information disclosure access detected</description>
    <mitre>
      <id>T1213</id>
    </mitre>
    <group>cve_2026_109526,information_disclosure,</group>
  </rule>

  <rule id="100527" level="7">
    <if_sid>100526</if_sid>
    <field name="parent_image">.*toonflow.*</field>
    <description>CVE-2026-109526: Low-privileged process triggered Toonflow-app exportData endpoint</description>
    <mitre>
      <id>T1213</id>
    </mitre>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). No vendor security advisory, commit, or CVE-to-fix mapping was confirmed in the tracked sources for this report. No workaround is documented in the provided data.

1. Immediate mitigations

   • Restrict local access to hosts running Toonflow-app ≤ 1.1.8 to trusted, fully-vetted users only. The exploit requires a local low-privileged session (PR:L, AV:L), so reducing untrusted local users directly reduces exposure.
   • Where feasible, constrain who can invoke the exportData functionality and monitor for invocations by non-administrative accounts.
   • Deploy the host-based detections in the Detection Guidance section to surface unauthorized local access attempts while a permanent resolution is evaluated.
   • If the application is not required, remove or disable Toonflow-app ≤ 1.1.8 from hosts.

2. Patch / upgrade steps

   • NVD states that upgrading to version 2.0.0 mitigates the issue. The vendor's current release is 2.0.4, resulting from a substantial architectural refactor; the vendor asserts the referenced code paths do not exist in the current version.
   • Because patch confidence is 0/4 and no vendor security advisory was confirmed, treat version upgrade as vendor-asserted mitigation rather than a formally coordinated patch. Validate that the target version (2.0.x) is a supported release in your deployment before relying on it as the fix.
   • For organizations that cannot move to 2.0.x, treat the system as permanently exposed for this issue and apply compensating controls (host access restriction, application removal, or isolation).

3. Long-term hardening

   • Enforce least privilege on hosts running desktop/native applications to limit the impact of local information-disclosure flaws.
   • Add automated version tracking and lifecycle management for the application so unsupported branches (such as 1.1.x) are retired.
   • Require authorization checks on all export/data-emission endpoints as a design principle; information-export functionality should scope returned records to the caller's entitlements.
   • Integrate local host telemetry (process lineage + command line) into the SOC to detect abuse of local-only vulnerabilities that network sensors cannot observe.

References

• NVD — CVE-2026-109526: https://nvd.nist.gov/vuln/detail/CVE-2026-109526
• CWE-200 — Exposure of Sensitive Information to an Unauthorized Actor: https://cwe.mitre.org/data/definitions/200.html
• FIRST EPSS — CVE-2026-109526 (not yet scored): https://api.first.org/data/v1/epss?cve=CVE-2026-109526
• CISA Known Exploited Vulnerabilities Catalog (CVE-2026-109526 is NOT listed): https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• Vendor product homepage / release channel — HBAI-Ltd Toonflow-app (verify current supported release, 2.0.4 as stated by vendor)