插件名称	ERI File Library
漏洞类型	Unauthenticated download vulnerability
CVE 编号	CVE-2025-12041
急	低的
CVE 发布日期	2025-10-31
源网址	CVE-2025-12041

ERI File Library (≤ 1.1.0) — Missing Authorization Allows Unauthenticated Protected File Download (CVE-2025-12041)

As the WP-Firewall security team, we track and respond to WordPress plugin vulnerabilities that can expose sensitive data or lead to compromise. On 31 October 2025 a Broken Access Control vulnerability affecting the ERI File Library plugin (versions ≤ 1.1.0, fixed in 1.1.1) was published (CVE-2025-12041). The issue allows unauthenticated users to download files that were intended to be protected by the plugin due to missing or incorrect authorization checks.

This post explains:

• What this vulnerability means for WordPress site owners
• How attackers can leverage it (conceptual overview — no exploit code)
• Practical detection methods and indicators of compromise
• Immediate and long-term mitigations, including virtual patching rules you can apply on the edge
• How WP-Firewall can protect your site (including our free plan)

We write with tangible, actionable guidance — not theory. If you maintain sites that use ERI File Library (or similar file-management plugins), treat this as a priority for review and remediation.

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Executive summary (what you need to know)

• 漏洞： Broken Access Control — missing authorization check for file downloads.
• 受影響的版本： ERI File Library ≤ 1.1.0
• 已修復： 1.1.1
• CVE: CVE-2025-12041
• Privilege required: Unauthenticated (no login required)
• Risk: Confidential/protected files may be downloaded by anyone who can reach the plugin’s download endpoint.
• Immediate action: Update the plugin to 1.1.1 or later. If you cannot update immediately, apply temporary access controls at the webserver/WAF level or restrict the plugin path until a safe update is possible.

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What the vulnerability actually is (plain language)

Plugins that offer file storage and downloads must perform two checks before serving a protected file:

1. Authentication (is the user logged in?)
2. Authorization (does the user have permission to access this specific file?)

This vulnerability is a classic missing-authorization issue: the plugin exposes a download endpoint that serves files but fails to verify that the requestor has permission to access the requested resource. That can allow anonymous visitors or crawlers to enumerate or directly download files that were intended to be private (customer documents, invoices, private images, attachments, etc.).

Unlike an RCE or SQL injection, this vulnerability’s most immediate risk is data exposure. However, exposed files can contain sensitive configuration or credentials, and exposure can be leveraged as part of a larger attack chain.

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How an attacker would typically abuse this (conceptual)

• The attacker locates the plugin’s download endpoint (common patterns include plugin directories or AJAX endpoints used by the plugin).
• They craft requests referencing file identifiers (IDs, tokens, file names, or paths) to that endpoint.
• Because the plugin does not enforce authorization, the server responds with the file content for requests regardless of authentication.
• The attacker can then download protected files, possibly in bulk, by enumerating file IDs or by attempting file path guesses.

We will not provide exploit code or step-by-step instructions to exploit this vulnerability. Instead, the guidance below focuses on detection, mitigation, and recovery.

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Exploitability and impact analysis

• Exploitability: High for data access — relatively straightforward if the plugin uses predictable identifiers or if a list of file IDs is discoverable. However, practical exploitation depends on how the plugin stores and references files (ID patterns, token complexity, etc.).
• 影響： Confidentiality breach. Exposed files may include PII, financial documents, private images, or other protected assets. In some cases, files themselves could contain secrets (API keys, SSH keys, or environment files) which can amplify the impact.
• CVSS: The published CVSS score for this report is 5.3 (Medium/Low depending on context) — a reasonable baseline. Site-specific risk can be higher if the website stores sensitive client data.

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Detection and indicators of compromise (what to look for)

Check the following sources to determine whether this issue has been abused on your site:

1. Webserver access logs (Apache, Nginx)
   • Frequent GET requests to plugin paths, e.g. requests containing /wp-content/plugins/eri-file-library/ or query parameters indicating a download action (id, file, token, file_id, download).
   • Large numbers of 200 responses for requests to download endpoints from previously anonymous IPs.
   • Requests to download large or sensitive file types (.pdf, .xls, .xlsx, .csv, .sql, .env, .pem, .zip) from non-authenticated sources.

   Example grep patterns:

   # Search for possible access to plugin endpoints
   grep -E "eri-file-library|eri_file_library|file_library" /var/log/nginx/access.log
   
   # Search for downloads of sensitive extensions
   grep -E "\.pdf|\.xls|\.xlsx|\.csv|\.env|\.sql|\.pem|\.zip" /var/log/nginx/access.log | grep -i "eri-file-library"
     

2. Application logs
   • Plugin logs (if available) showing download requests without an associated user or showing missing/session anomalies.
   • Unusual spikes in admin-ajax requests that include file identifiers.
3. Hosting control panel / storage logs
   • Object storage access logs (S3, DigitalOcean Spaces) showing direct downloads mapped to plugin-managed objects.
   • File system timestamps: creation/last read of protected files at times corresponding to suspicious IPs.
4. Analytics and SIEM
   • Page metrics or analytics events for file download endpoints originating from new / suspicious IPs or geographies.
5. User reports
   • End-users reporting leaked files or receiving access notifications they did not expect.

If any of the above indicate suspicious downloads, immediately preserve logs and take action (see Incident Response below).

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Immediate mitigation steps (short term)

If you cannot update the plugin immediately to 1.1.1, apply one or more of these temporary mitigations to block unauthenticated access:

1. Update the plugin
   • The simplest, most reliable fix: update ERI File Library to version 1.1.1 or later on all sites as soon as possible.
2. Block or restrict plugin endpoints at the webserver/WAF level
   • Deny public access to the plugin folder or download endpoints unless authenticated. Use IP allowlists, basic auth, or block all public access and allow only admin IPs until you update.
3. Require WordPress login cookie for downloads (temporary WAF rule)
   • On the edge (WAF or webserver) block requests to the plugin download endpoint that lack WordPress authenticated cookies (cookies beginning with wordpress_logged_in_). This is a practical short-term filter; it is not foolproof but reduces anonymous exploitation.
4. Move protected files out of the webroot
   • If plugin settings allow, move private assets outside of the public web directory so they cannot be fetched via simple HTTP GETs.
5. Disable plugin while you patch
   • If you cannot mitigate otherwise and the plugin is not critical, temporarily deactivate it until you can update.
6. Limit file types
   • If possible, remove/relocate extremely sensitive files (.env, .sql, .pem) that may have been stored by accident.

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Virtual patching and WAF rules — recommended signatures

Below are example rules you can use as virtual patches on a WAF or web application firewall layer (Apache mod_security, Nginx with ngx_http_lua_module, or your managed WAF). These should be deployed as temporary protections until the plugin is updated. Test rules in monitoring mode before blocking to avoid false positives.

重要： adapt paths and argument names to match how ERI File Library is configured on your site.

ModSecurity (example)

# Block unauthenticated access to ERI File Library download endpoints
SecRule REQUEST_URI "@rx /wp-content/plugins/eri-file-library/|/wp-admin/admin-ajax.php" \
  "phase:1,chain,deny,log,status:403,msg:'Blocked unauth file download attempt (ERI File Library)'"
  SecRule ARGS_NAMES|ARGS "@rx (file|file_id|id|download|token)" "chain"
  SecRule REQUEST_HEADERS:Cookie "!@rx wordpress_logged_in_"

• Explanation:
• Match requests to likely plugin URIs or admin-ajax (adjust to your environment).
• Look for query parameters commonly used for downloads.
• Deny when no WordPress login cookie is present.

Nginx (location block) — simple blocking by path

# Deny access to plugin download endpoint (temporary)
location ~* /wp-content/plugins/eri-file-library/.*download.* {
    return 403;
}

# Or deny direct access to plugin's download script
location = /wp-content/plugins/eri-file-library/download.php {
    return 403;
}

Nginx + Lua (cookie-based check)

If your edge supports Lua, inspect the Cookie header for wordpress_logged_in_:

access_by_lua_block {
  local uri = ngx.var.request_uri
  if uri:find("eri%-file%-library") or uri:find("download") then
    local cookie = ngx.var.http_cookie or ""
    if not cookie:find("wordpress_logged_in_") then
      ngx.log(ngx.ERR, "Blocked unauthenticated access to ERI File Library download endpoint")
      return ngx.exit(403)
    end
  end
}

Notes:

• These are temporary safeguards. A cookie check merely enforces “authenticated user” presence, not whether the authenticated user is authorized for a specific file.
• If your environment cannot safely use these rules, prefer disabling the plugin or restricting access by IP ranges.

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Long-term mitigation and secure design recommendations

Site owners should take the opportunity to check their file-management policy and harden how private assets are served.

1. Enforce proper server-side authorization
   • Every file-download flow must verify both authentication and fine-grained authorization: check that the current user has rights to access the specific file (owner or role-based permission).
2. Use non-guessable tokens
   • If downloads are offered via temporary URLs, ensure tokens are long, random, single-use or time-limited.
3. Store sensitive files outside the web root
   • Use protected storage and serve files through a controlled script that enforces permission checks. Prefer webserver X-Accel-Redirect or X-Sendfile patterns where the application authorizes then instructs the server to deliver the file.
4. Audit plugin permissions and file upload code
   • Confirm that file uploads and file listing functions don’t leak file identifiers or expose directory indexes.
5. Use least-privilege principles
   • Administrative operations should require admin-level capabilities. Avoid allowing broadly scoped roles to access or enumerate file lists.
6. Regularly review plugin updates
   • Have a schedule/automation for plugin updates. Critical security fixes should be installed promptly.

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Incident response checklist (if you detect suspicious downloads)

If you suspect you were impacted, follow this incident response outline:

1. Preserve logs
   • Copy relevant access and error logs to a safe offline location for forensic analysis.
2. Patch immediately
   • Update ERI File Library to 1.1.1 or later. If that is not possible, disable the plugin or apply WAF rules as described above.
3. Identify exposed files
   • Use logs to enumerate which files were requested and successfully served. Cross-check with file inventory to find sensitive items.
4. Assess the impact
   • Determine whether exposed files contain PII, secrets, or financial data. Classify the severity accordingly.
5. Notify affected parties
   • If PII or regulated data was exposed, comply with any legal or contractual reporting obligations.
6. Rotate keys
   • If files contain API keys, tokens, or credentials, rotate those credentials immediately (database passwords, API keys, certificates).
7. Malware scan and integrity check
   • Scan for modified or added files. Ensure there is no follow-up malware planted as a result of the access.
8. Harden and monitor
   • Apply the long-term mitigations above and increase monitoring for suspicious activity.
9. Post-incident review
   • Document root cause and update procedures so the same mistake does not recur (e.g., secure development guidelines and plugin hardening checklist).

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Recommended log-search queries (practical)

Quick searches you can run on typical Linux hosting to find suspicious download activity. Update patterns as needed.

• Find GET requests with ‘download’ or ‘file’ in query:

grep -iE "download|file|file_id|fileid|token" /var/log/nginx/access.log | grep -i "eri-file-library"

• Find requests for common sensitive extensions served from plugin-related URIs:

grep -iE "eri-file-library" /var/log/nginx/access.log | grep -E "\.pdf|\.xls|\.xlsx|\.csv|\.env|\.sql|\.pem|\.zip"

• Count unique IPs requesting downloads in the last 7 days:

grep -i "eri-file-library" /var/log/nginx/access.log | awk '{print $1}' | sort | uniq -c | sort -nr | head -n 50

• Identify large responses (possible file downloads):

awk '$10 ~ /^[0-9]+$/ && $10 > 1000000 {print $0}' /var/log/nginx/access.log | grep "eri-file-library"

(Adjust log field indexes according to your Nginx/Apache log format.)

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How WP-Firewall protects you (our approach)

At WP-Firewall we provide layered defenses designed to reduce the window of exposure for issues like this one:

• Managed WAF ruleset tailored for WordPress — we deploy virtual patch signatures for known vulnerabilities and rapidly update rules when new issues are published.
• Auto-mitigation of common file-access abuse patterns — our rules detect anomalous access to plugin download endpoints and can block unauthenticated downloads until a site is updated.
• Malware scanning and file integrity checks — we surface changes to the filesystem and quickly highlight unknown or unexpected files that might have been exposed or uploaded.
• Traffic analytics and alerting — detect spikes in download activity and the IPs involved so you can investigate quickly.
• Hands-on recommendations — we provide step-by-step remediation guidance for sysadmins and site owners.

If you run multiple WordPress sites or host third-party plugins, deploying a managed edge protection layer dramatically reduces the risk that missing authorization or similar logic bugs will lead directly to data leaks.

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Example detection rules we run (conceptual)

Here are several detection heuristics that any advanced WAF should consider for file-download protection:

• Flag requests to plugin download endpoints when:
  • No wordpress_logged_in_ cookie is present AND
  • The request has query params commonly used for file identification AND
  • Response size > 50KB (indicates actual file content returned)
• Rate-limit repeated requests for different file IDs from a single IP:
  • > 50 distinct file download requests per hour -> throttle/block
• Alert on enumerations:
  • Many 200 responses to sequential numeric IDs (e.g., id=100, id=101, id=102) suggests enumeration.
• Detect token brute force:
  • Multiple attempts to guess token values for download endpoints from same IP.

These heuristics can be tuned to your environment. We recommend starting in monitoring mode to measure baseline behavior before switching to block mode.

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Hardening checklist you should perform now

• Update ERI File Library to 1.1.1 or later on every site.
• Review sensitive files stored in plugin-controlled areas and relocate them if needed.
• Audit plugin code (or request vendor confirmation) to ensure authorization checks are present for any file-serving controller.
• Add WAF rules to block unauthenticated access to plugin endpoints until patched.
• Scan the site for exposed PII or secrets and rotate any exposed credentials.
• Maintain backups and enable file integrity monitoring.
• Configure alerts for unusual spikes in download activity.

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Why you should act quickly (risk reminders)

• The vulnerability requires no authentication — it’s accessible to anyone who can reach your site.
• Attackers frequently scan the web for plugin endpoints and attempt automated downloads. A small window can lead to bulk data leakage.
• Exposed files may contain secrets that enable further compromise (credential reuse is common).

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Below is a short promotional paragraph you can include on your site or newsletter. It’s written to fit naturally within a security advisory without sounding like a hard sell.

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Final thoughts — responsible steps for plugin consumers and developers

對於網站所有者：

• Treat private files as crown jewels. Even a plugin meant to simplify file delivery can leak data if authorization is overlooked.
• Keep plugins updated and monitor access to plugin-specific endpoints.
• Use a layered defense model: code-level authorization, hosting configuration (storage outside webroot), and WAF/edge protections.

For plugin developers:

• Validate both authentication and authorization for every file-serving action.
• Use non-guessable identifiers for files and time-limited download tokens where appropriate.
• Run threat modelling and incorporate permission checks into unit and integration tests (automated tests should simulate unauthenticated requests and assert denial).
• Provide clear changelogs and security notices — and promptly patch and communicate fixes.

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If you run sites that use the ERI File Library plugin, the single best action is to update to 1.1.1 immediately. If you need help assessing exposure, hardening servers, or setting up virtual patching while you patch, the WP-Firewall team is available to help — and our Free plan gives you immediate baseline protection while you make the upgrade.

For technical assistance or to enable virtual patching across multiple sites, you can sign up here:
https://my.wp-firewall.com/buy/wp-firewall-free-plan/

保持安全，
WP-Firewall 安全團隊

(End of advisory)