| Nom du plugin | WP RSS Aggregator |
|---|---|
| Type de vulnérabilité | Script intersite (XSS) |
| Numéro CVE | CVE-2025-14375 |
| Urgence | Moyen |
| Date de publication CVE | 2026-01-18 |
| URL source | CVE-2025-14375 |
Reflected XSS in WP RSS Aggregator (CVE‑2025‑14375) — What WordPress Site Owners Need to Know and Do Now
Author’s note (Hong Kong security practitioner tone): This advisory is written from the perspective of a security professional based in Hong Kong with practical, defensive advice for site owners and administrators. The aim is to be concise, clear and action‑oriented so you can prioritise remediation across multiple sites quickly.
TL;DR
- A reflected Cross‑Site Scripting (XSS) vulnerability (CVE‑2025‑14375) was disclosed in the WP RSS Aggregator plugin affecting versions ≤ 5.0.10; fixed in 5.0.11.
- Root cause: untrusted input reflected into an HTML attribute (className) without proper encoding/validation, allowing script injection when a victim opens a crafted URL or feed-related page.
- CVSS: 7.1 (Medium). Vector: AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L — remote, low complexity, unauthenticated attacker, but requires user interaction.
- Immediate actions: update plugin to 5.0.11+, or apply virtual patching via WAF rules, add restrictive CSP, lock down feed/import endpoints, and monitor logs.
Why this matters (brief)
Reflected XSS remains a frequent and effective method for attackers to execute JavaScript in a visitor’s browser. Although exploitation typically requires a victim to click a crafted link or view a manipulated page, the impacts can include session theft, unauthorised actions performed on behalf of users, and client‑side malware delivery.
This vulnerability affects WP RSS Aggregator (RSS Import, News Feeds, Feed to Post, Autoblogging functionality) up to and including version 5.0.10. Any site that exposes feed or import endpoints or renders externally supplied feed content in admin or public UI may be at risk.
Résumé de la vulnérabilité
- Identifiant : CVE‑2025‑14375
- Product: WP RSS Aggregator (WordPress plugin)
- Versions affectées : ≤ 5.0.10
- Corrigé dans : 5.0.11
- Type : Reflected Cross‑Site Scripting (XSS) via className attribute / parameter
- CVSS base score: 7.1 (Medium)
- Date de divulgation : January 16, 2026 (security advisory published)
In short: unsanitised/unencoded input is reflected into an HTML attribute labelled className (or similar), enabling injection of HTML/JavaScript that executes in a victim’s browser when they visit a crafted link or view content that contains the payload.
How the vulnerability typically works (technical overview — defensive focus)
Reflected XSS happens when an application takes untrusted data from a request (URL, headers, form fields, feed content), embeds it into a response without proper encoding, and returns it to the client. In this case, the plugin reflected a value into an element attribute (reported as className) that should not be populated directly from external input without sanitisation.
Points techniques clés :
- The vulnerable code concatenates a string derived from an incoming request or feed into a DOM/HTML attribute.
- Input is not validated to disallow HTML special characters (
<,>,",',/) or event handler attributes (e.g.au chargement,onclick). - Because the value is reflected directly in the response, an attacker can craft a URL that causes injected script to run in a victim’s browser when they click it or preview a feed.
- Successful exploitation can result in data theft (cookies/localStorage), CSRF-like actions, or further payload delivery.
Note: The bug is “reflected” — not stored — meaning the malicious content is sent in a request and immediately reflected back. However, if crafted links are indexed, cached, or logged, the effect can appear persistent.
Exploitation scenarios and risks
Qui est à risque ?
- Sites running WP RSS Aggregator ≤ 5.0.10.
- Sites where administrators or privileged users view feed import pages, feed previews, or plugin pages that render external content.
- Sites that expose feed endpoints publicly and allow importing arbitrary feeds without validation.
Possible attacker goals
- Steal authentication cookies or session tokens (account takeover).
- Perform actions in the context of a user (create posts, change settings) by combining XSS with CSRF or other methods.
- Deliver phishing content, redirects, or malicious ads.
- Install client‑side malware targeting visitors.
Why attackers can use this
- Remote and unauthenticated: attackers can craft links without needing a WordPress account.
- Low complexity: simple reflection of special characters into HTML can produce execution.
- Requires user interaction: attackers typically social‑engineer administrators or contributors into visiting a crafted link.
Safe testing and proof‑of‑concept guidance (for defenders)
Only test on a staging or isolated environment. Never run exploit tests against production sites with real users.
High‑level defensive testing steps:
- Clone your site or set up a clean WordPress instance and install the same plugin version (≤ 5.0.10).
- Access feed or page endpoints that may render external input.
- Use benign payloads (display‑only markers) to confirm where input is reflected.
- Check whether HTML special characters appear unencoded in responses.
- If a non‑executing marker is reflected, the site is vulnerable — proceed to update or mitigate.
Do not publish working exploit code. Use inert markers to confirm reflection and then remediate.
What to do immediately (priority checklist)
- Update the plugin (preferred, immediate fix): Upgrade WP RSS Aggregator to version 5.0.11 or later as soon as possible on all affected sites.
- If you cannot update immediately — apply mitigations:
- Apply WAF rules (virtual patch) to block requests that include angle brackets, event handlers, or JavaScript protocols in fields expected to be class names.
- Add or tighten a Content Security Policy (CSP) to restrict inline script execution and limit script sources.
- Restrict access to feed importer/admin pages using IP allow‑listing or limiting to authenticated administrators.
- Temporarily disable or pause imports from untrusted sources until patched.
- Rotate credentials and review sessions: If you suspect targeting, force password resets for affected accounts and invalidate active sessions.
- Scan and monitor: Run malware scans and review server logs for suspicious requests referencing feed endpoints or className-like parameters with encoded payloads.
- Informez les parties prenantes : Notify clients or colleagues and schedule an update window. Prioritise high‑traffic and public feed exposure sites.
Recommended WAF rules and hardening (examples)
Below are defensive rules and configurations you can use to mitigate this vulnerability until the plugin is updated. Adapt and test in staging before deploying to production.
Generic ModSecurity-style rule to block angle brackets or event handlers within class-like parameters:
# Block requests containing suspicious characters in common parameters like class, className, classname
SecRule ARGS_NAMES "(?i)(classname|className|class)" "phase:2,deny,status:403,log,chain,msg:'Block potential XSS via className parameter'
SecRule ARGS(classname|className|class) \"@rx (<|>|javascript:|\\bon\\w+=)\""
Block common XSS payloads in request data:
SecRule REQUEST_URI|ARGS|ARGS_NAMES|REQUEST_HEADERS "@rx (CSP header recommendation (start with a restrictive policy; use report-only mode to test):
Content-Security-Policy: default-src 'self'; script-src 'self' https://trusted.cdn.example.com; object-src 'none'; base-uri 'self'; report-uri /csp-report-endpoint;
Notes:
- These rules may block legitimate traffic if applied too broadly — test and tune carefully.
- Use layered controls: WAF rules + CSP + server-side input validation.
Developer guidance — how the plugin should have prevented this
If you develop or maintain plugins or themes that render user-supplied content, follow these principles:
- Output encoding
Encode data before inserting into HTML. For attributes use proper attribute encoding. In WordPress PHP templates, use:
// Unsafe echo '<div class="'.$user_input.'">'; // Safe echo '<div class="'.esc_attr( $user_input ).'">'; - Validate and sanitise inputs
For known value sets (e.g., CSS class names), whitelist acceptable characters and lengths:
$safe_class = preg_replace( '/[^a-z0-9\-_ ]/i', '', $raw_class ); - Avoid reflecting raw feed content in admin pages without sanitisation
Treat all feed or external content as untrusted and escape before rendering.
- Use nonces and capability checks
Ensure only authenticated, authorised users can perform import operations or render administrative previews.
- Use CSP for defence‑in‑depth
Even with correct encoding, CSP reduces impact if errors occur by preventing inline scripts or restricting script sources.
Detecting exploitation and indicators of compromise (IoCs)
What to look for in logs and monitoring:
- Requests to feed or plugin endpoints with encoded payloads containing
%3C,%3E,javascript:, oronload=. - Unexpected admin actions or configuration changes after administrators report clicking links.
- New or unexpected JavaScript appearing on pages (inspect source / DOM).
- Suspicious outbound requests from admin browsers to attacker domains after admin activity.
- New users/roles, changed content, or altered plugin settings without authorisation.
If you find signs of compromise:
- Take the site offline or block public access temporarily.
- Revoke admin sessions and reset credentials.
- Restore from a known clean backup if necessary.
- Conduct a forensic review to identify vector and scope.
Long‑term hardening recommendations for WordPress site owners
- Keep themes, plugins and WordPress core updated promptly. Maintain a security update workflow.
- Limit plugin usage to necessary, actively maintained components and remove unused plugins.
- Apply principle of least privilege for user accounts; avoid using administrator accounts for routine tasks.
- Implement layered defenses: WAF, CSP, server‑side validation, secure wp-config.php, PHP hardening, and regular malware scans.
- Maintain automated backups and an incident response plan for quick recovery.
- Periodically audit plugin usage, run vulnerability scans and monitor server logs.
Virtual patching and why it helps
Virtual patching (edge blocking via WAF or similar controls) provides an immediate option to reduce risk when updating across many sites is not yet possible. Key benefits:
- Stops attack patterns before they reach the vulnerable application code.
- No dependency on immediate code changes across multiple sites.
- Allows targeted rules for specific endpoints, reducing broader disruption.
- Provides visibility into attack attempts, which helps prioritise remediation.
Virtual patching is a stopgap — the correct long‑term fix is to update the plugin. Use virtual patches alongside monitoring and patch deployment plans.
Practical upgrade and mitigation checklist (step‑by‑step)
- Schedule maintenance if needed and inform stakeholders.
- Backup site files and database.
- Update WP RSS Aggregator to >= 5.0.11.
- If unable to update immediately:
- Deploy WAF/edge rules that block typical XSS payloads in class-like parameters and feed content.
- Add CSP headers restricting inline scripts (start with report‑only mode to audit).
- Restrict access to plugin admin pages via IP allow‑listing or firewall rules.
- Rotate admin passwords and revoke stale sessions.
- Review logs for suspicious requests matching exploit patterns and respond accordingly.
- Re-test pages and admin flows to ensure mitigations don’t break critical functionality.
- Document steps taken and timeline for stakeholders.
Frequently asked questions
Q: I updated — do I still need WAF?
A: Updating removes this specific vulnerability in the plugin, but a WAF adds a layer of defence against unknown or future issues and can block exploitation attempts while you test updates.
Q: Will enabling CSP break my site?
A: A poorly configured CSP can break functionality. Start with report‑only to observe violations, then progressively enforce the policy.
Q: Is reflected XSS always exploitable across users?
A: No. Exploitation depends on a victim visiting a crafted link or previewing content. Attackers often target high‑value users (administrators), so even reflected XSS is dangerous.
Q: My site uses caching/CDN — does that matter?
A: Yes. Caches can serve maliciously crafted content to other users if edge layers cache pages containing reflected inputs. Ensure caching rules don’t store responses that include untrusted request data.
Final thoughts
Reflected XSS vulnerabilities like CVE‑2025‑14375 highlight the need for layered security and rapid response. The highest‑impact action is to update WP RSS Aggregator to version 5.0.11 or later. If immediate updates are impractical across many sites, apply virtual patching via WAF, implement CSP, and restrict access to feed/import interfaces to substantially reduce risk.
For teams managing multiple sites, adopt a consistent update, monitoring and incident response policy to reduce exposure windows. Remember: virtual patches and WAFs are mitigation strategies, not substitutes for secure coding and timely plugin maintenance.
Stay vigilant, treat external content as hostile until sanitised, and prioritise remediation for administrator‑facing pages.
