CVE-2026-76215

Executive Summary

CVE-2026-76215 is an authorization bypass vulnerability in phpMyFAQ versions prior to 4.1.7, affecting the comments and attachments API endpoints. The flaw allows unauthenticated attackers to retrieve restricted comment text, commenter email addresses, and attachment filenames for FAQ records they cannot directly access. The vulnerability has a CVSS score of 5.3 (Medium) with a low confidentiality impact, and no evidence of exploitation in the wild has been reported at this time.

Technical Analysis

Vulnerability Mechanism

The vulnerability is classified under CWE-862 (Missing Authorization), indicating that the application fails to enforce proper access control checks on certain API endpoints. Specifically, phpMyFAQ before version 4.1.7 does not apply parent FAQ visibility checks before returning child resources — namely comments and attachments — associated with FAQ records.

Root Cause

The root cause lies in the API layer's resource-handling logic. When a user (or unauthenticated attacker) queries the comments or attachments API endpoints, the application retrieves and returns data without first verifying whether the parent FAQ record is publicly visible or accessible to the requesting party. This constitutes a classic missing-authorization flaw where:

1. The parent FAQ record has visibility restrictions (e.g., restricted to logged-in users, specific groups, or categories).
2. The child resources (comments, attachments) are served from separate endpoints that bypass the parent's visibility check.
3. The API returns sensitive child-resource data regardless of the requester's authorization level.

Sensitive Data Exposed

Based on the NVD description, the following data is exposed through these API endpoints:

• Restricted comment text: Comments associated with FAQ records that the attacker cannot directly access.
• Commenter email addresses: Email addresses of users who posted comments on restricted FAQs.
• Attachment filenames: Filenames of attachments linked to restricted FAQ records.

While attachment filenames alone may seem low-severity, they can leak information about internal document naming conventions (e.g., filename patterns revealing project names, client names, or document classification).

Attack Surface

The attack surface is the phpMyFAQ web application's comments and attachments API endpoints, which are reachable over the network. The CVSS vector AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N confirms:

• Network-accessible (AV:N)
• Low attack complexity (AC:L) — no special conditions required
• No privileges required (PR:N) — unauthenticated exploitation
• No user interaction (UI:N)
• Unchanged scope (S:U)
• Low confidentiality impact (C:L)
• No integrity or availability impact (I:N, A:N)

Exploitation Scenarios

Step 1: Reconnaissance / Target Identification

An attacker identifies internet-facing phpMyFAQ installations using:

• Shodan/Censys searches for HTTP titles or body content containing "phpMyFAQ"
• Google dorking: intitle:"phpMyFAQ" or inurl:"index.php?action=faq"
• Banner grabbing to confirm the version (if version disclosure is enabled)

Step 2: Triggering the Authorization Bypass

Since this is an authorization bypass vulnerability at the API level, the attacker does not need to authenticate. The attack proceeds as follows:

• The attacker enumerates FAQ record IDs (commonly sequential integers, e.g., 1, 2, 3...).
• For each FAQ ID, the attacker queries the comments and attachments API endpoints directly.
• The API returns the associated comment data and attachment metadata without verifying the visibility settings of the parent FAQ record.

Note: Specific endpoint paths and parameter names are not documented in the NVD description. The attack is performed against whatever URI structure phpMyFAQ uses for its API (e.g., /api/comments/{faqId} and /api/attachments/{faqId} — exact paths not verifiable from available data).

Step 3: Payload / Execution Method

This is not an injection-based vulnerability; no payload is required. The attack involves:

1. Crafting HTTP GET requests to the API endpoints for each FAQ ID.
2. Parsing the JSON/XML responses for comment text, email addresses, and attachment filenames.
3. Automating the enumeration across the full range of FAQ IDs using a script (e.g., curl loop or Python requests).

Step 4: Post-Exploitation Impact

Post-exploitation impact depends on the sensitivity of the leaks:

• Comment text: May contain internal discussions, troubleshooting notes, or sensitive customer information.
• Email addresses: Enables targeted phishing campaigns against commenters (both admins and users).
• Attachment filenames: Leaks organizational information; may aid further attacks (e.g., guessing other document names on the server if directory traversal or information disclosure exists elsewhere).

PoC Status: No public PoC is available; attack chain is inferred from the vulnerability class (missing authorization on child resources).

Impact Assessment

Business Impact

• Confidentiality breach: Restricted FAQ content — specifically comments and attachment metadata — becomes readable by anyone, bypassing the FAQ author's intent for restricted visibility.
• Privacy violation: Commenter email addresses are exposed, potentially violating data protection regulations (GDPR, CCPA) if the commenters are EU/California residents.
• Reputational risk: Organizations relying on phpMyFAQ for internal knowledge management may have sensitive operational details leaked.
• Information leakage for further attacks: Comment text often contains technical details (error messages, server paths, version numbers) useful for subsequent exploitation.

CVSS Subscore Analysis

• CVSS 5.3 (Medium): The score reflects low direct impact (L for confidentiality, N for integrity/availability). However, the business context may elevate the severity — leaked emails enable phishing, and leaked comments may contain credentials or internal architecture details.

Blast Radius

• Affected systems: All phpMyFAQ installations running versions prior to 4.1.7.
• Exposed data: Comments, commenter emails, and attachment filenames for FAQ records marked as restricted or non-public.
• Attack scope: Any network-reachable phpMyFAQ instance, regardless of authentication requirements for the main FAQ interface.

Detection Guidance

Sigma Rule

title: phpMyFAQ API Unauthenticated Child Resource Access (CVE-2026-76215)
id: 5b8d2f4a-1c3e-4a7f-9b2d-8e6f1c4a7b3e
status: experimental
description: Detects unauthenticated requests to phpMyFAQ comments and attachments API endpoints in a rapid sequence, suggesting enumeration of FAQ IDs to exploit CVE-2026-76215.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-76215
tags:
    - attack.t1190
    - attack.collection
logsource:
    category: webserver
    product: apache
    definition: Web server access logs for phpMyFAQ deployments
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains|all:
            - 'comments'
            - 'api'
            - 'faq'
    selection_alternative:
        cs-method: 'GET'
        cs-uri-query|contains|all:
            - 'attachments'
            - 'api'
            - 'faq'
    condition: selection OR selection_alternative
    timeframe: 30s
level: medium
falsepositives:
    - Legitimate user activity if the API is used legitimately without authentication checks in non-restricted FAQ setups
fields:
    - c-ip
    - cs-uri-query
    - cs-method

YARA Rule

rule phpMyFAQ_CVE_2026_76215_ExploitAttempt
{
    meta:
        author = "Valters IT Security"
        description = "Detects potential exploit attempts for CVE-2026-76215 in phpMyFAQ by identifying HTTP request patterns targeting comments and attachments API endpoints"
        date = "2026-02-01"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-76215"
        severity = "medium"
        cve = "CVE-2026-76215"
    strings:
        $s1 = "comments" ascii wide nocase
        $s2 = "attachments" ascii wide nocase
        $s3 = "api" ascii wide nocase
        $s4 = "GET /" ascii wide
        $s5 = "faq" ascii wide nocase
    condition:
        uint16(0) == 0x0A0D and
        2 of ($s1, $s2) and
        $s3 and
        $s4 and
        $s5 and
        filesize < 1KB
}

Note: YARA is primarily for file scanning (e.g., log files, captured HTTP traffic). This rule targets raw HTTP request/response captures in PCAPs or web server logs containing full request lines.

Suricata IDS Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2026-76215 - phpMyFAQ Unauthenticated Child Resource Access Attempt";
    flow:to_server,established;
    http.method; content:"GET";
    http.uri; content:"comments"; nocase;
    http.uri; content:"api"; nocase;
    http.uri; content:"faq"; nocase;
    threshold:type both, track by_src, count 5, seconds 60;
    classtype:attempted-recon;
    reference:cve,2026-76215;
    reference:url,https://nvd.nist.gov/vuln/detail/CVE-2026-76215;
    sid:10000001;
    rev:1;
)

Alternate Suricata rule for attachments endpoint:

alert http any any -> $HOME_NET any (
    msg:"CVE-2026-76215 - phpMyFAQ Unauthenticated Attachment Metadata Enumeration";
    flow:to_server,established;
    http.method; content:"GET";
    http.uri; content:"attachments"; nocase;
    http.uri; content:"api"; nocase;
    threshold:type both, track by_src, count 5, seconds 60;
    classtype:attempted-recon;
    reference:cve,2026-76215;
    sid:10000002;
    rev:1;
)

Elastic Detection

// Detection of rapid sequential API requests to phpMyFAQ comments/attachments endpoints
sequence by source.ip with maxspan=60s
  [network where host.os.name == "Linux" and network.protocol == "http" and
   http.request.method == "GET" and
   http.request.uri contains "api" and
   (http.request.uri contains "comments" or http.request.uri contains "attachments") and
   http.request.uri contains "faq"]
  [network where host.os.name == "Linux" and network.protocol == "http" and
   http.request.method == "GET" and
   http.request.uri contains "api" and
   (http.request.uri contains "comments" or http.request.uri contains "attachments") and
   http.request.uri contains "faq"]
  [network where host.os.name == "Linux" and network.protocol == "http" and
   http.request.method == "GET" and
   http.request.uri contains "api" and
   (http.request.uri contains "comments" or http.request.uri contains "attachments") and
   http.request.uri contains "faq"]

Splunk SPL Query

index=web sourcetype=access_combined
| where like(uri_path, "%api%") AND (like(uri_path, "%comments%") OR like(uri_path, "%attachments%")) AND like(uri_path, "%faq%")
| eval faq_id = regex_extract(uri_path, "(\d+)")
| stats count by clientip, faq_id
| where count > 5
| table _time, clientip, faq_id, count
| sort - count
| eval alert_message = "Potential CVE-2026-76215 enumeration detected: " + tostring(count) + " API requests by " + clientip

Wazuh OSSEC Rule

<group name="web,phpmyfaq,cve-2026-76215,">
  <rule id="100301" level="8">
    <decoded_as>web</decoded_as>
    <description>phpMyFAQ API enumeration attempt (CVE-2026-76215)</description>
    <match>GET</match>
    <match>api</match>
    <regex>comments|attachments</regex>
    <regex>\d+</regex>
    <group>access-control,web_application_attack,</group>
    <mitre>
      <id>T1190</id>
    </mitre>
    <info>Unauthenticated requests to phpMyFAQ comments/attachments API endpoints detected. Multiple requests suggest enumeration.</info>
    <options>no_full_log</options>
    <frequency>5</frequency>
    <timeframe>60</timeframe>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Status

Patch confidence: 0/4 — UNPATCHED. No patch evidence from any tracked source was identified. The NVD description indicates the vulnerability exists in versions before 4.1.7, implying version 4.1.7 is the patched release; however, as of this report's generation, no vendor advisory or official patch confirmation has been published.

1) Immediate Mitigations (No Patch Available)

• Restrict network access: Place phpMyFAQ behind a VPN or restrict access to trusted IP ranges at the firewall/reverse proxy level.
• Disable or gate the API: If feasible, block access to the comments and attachments API endpoints at the WAF or reverse proxy level for unauthenticated users.
• Web Application Firewall (WAF) rules: Deploy custom WAF rules to block rapid sequential GET requests to API endpoints containing "comments" or "attachments".
• Rate limiting: Enable rate limiting on the web server to slow down enumeration attempts.
• Vendor notification: Contact the phpMyFAQ maintainers to inquire about the fix status and any pre-release patch availability.

2) Patch / Upgrade Steps

• Upgrade phpMyFAQ to version 4.1.7 or later once the patched release is confirmed available and tested.
• Prior to upgrading, review the phpMyFAQ release notes and changelog for 4.1.7 to confirm that the fix addresses CVE-2026-76215.

3) Long-Term Hardening

• Configuration audit: Review FAQ visibility settings; ensure that restricted FAQs are not inadvertently accessible via API endpoints.
• Security testing: Conduct regular penetration testing of the phpMyFAQ instance, focusing on API endpoints and authorization checks.
• Version monitoring: Subscribe to phpMyFAQ security announcements to stay informed of future vulnerabilities and patches.
• Least-privilege principle: Limit commenter and attachment data exposure by minimizing the sensitivity of information stored in FAQ comments and attachment filenames.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2026-76215
2. CWE-862 (Missing Authorization): https://cwe.mitre.org/data/definitions/862.html
3. MITRE ATT&CK T1190 (Exploit Public-Facing Application): https://attack.mitre.org/techniques/T1190/
4. phpMyFAQ Official Site: https://www.phpmyfaq.de/
5. CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog (CVE-2026-76215 NOT listed — no known exploitation in the wild)

Report generated by Valters IT Security Threat Intelligence. No known threat actor campaigns or exploit-in-the-wild evidence has been identified for this CVE as of the report date. Technical details are limited to the NVD description; insufficient technical detail is available to identify specific endpoint paths or parameter names.