CWE-79 (在Web页面生成时对输入的转义处理不恰当(跨站脚本)) — Vulnerability Class 23852

23852 vulnerabilities classified as CWE-79 (在Web页面生成时对输入的转义处理不恰当(跨站脚本)). AI Chinese analysis included.

CWE-79 represents a critical input validation weakness where software fails to properly sanitize user-supplied data before rendering it in web pages. Attackers typically exploit this vulnerability by injecting malicious scripts, often JavaScript, into trusted websites. When other users view the compromised page, the embedded code executes in their browsers, allowing the attacker to steal session cookies, hijack accounts, or redirect victims to phishing sites. This breach of trust undermines user privacy and application integrity. To prevent such attacks, developers must implement robust input validation and output encoding strategies. By strictly filtering incoming data and ensuring that all dynamic content is properly escaped before being processed by the browser, developers can neutralize dangerous inputs and effectively mitigate the risk of cross-site scripting vulnerabilities.

MITRE CWE Description

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. There are many variants of cross-site scripting, characterized by a variety of terms or involving different attack topologies. However, they all indicate the same fundamental weakness: improper neutralization of dangerous input between the adversary and a victim.

Common Consequences (3)

Access Control, Confidentiality Bypass Protection Mechanism, Read Application Data

The most common attack performed with cross-site scripting involves the disclosure of private information stored in user cookies, such as session information. Typically, a malicious user will craft a client-side script, which -- when parsed by a web browser -- performs some activity on behalf of the…

Integrity, Confidentiality, Availability Execute Unauthorized Code or Commands

In some circumstances it may be possible to run arbitrary code on a victim's computer when cross-site scripting is combined with other flaws, for example, "drive-by hacking."

Confidentiality, Integrity, Availability, Access Control Execute Unauthorized Code or Commands, Bypass Protection Mechanism, Read Application Data

The consequence of an XSS attack is the same regardless of whether it is stored or reflected. The difference is in how the payload arrives at the server. XSS can cause a variety of problems for the end user that range in severity from an annoyance to complete account compromise. Some cross-site scri…

Mitigations (5)

Architecture and Design Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.

Implementation, Architecture and Design Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required e…

Architecture and Design, Implementation Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly throug…

Effectiveness: Limited

Architecture and Design For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Architecture and Design If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.

Examples (2)

The following code displays a welcome message on a web page based on the HTTP GET username parameter (covers a Reflected XSS (Type 1) scenario).

$username = $_GET['username']; echo '<div class="header"> Welcome, ' . $username . '</div>';

Bad · PHP

http://trustedSite.example.com/welcome.php?username=<Script Language="Javascript">alert("You've been attacked!");</Script>

Attack

The following code displays a Reflected XSS (Type 1) scenario.

<% String eid = request.getParameter("eid"); %> ... Employee ID: <%= eid %>

Bad · JSP

<% protected System.Web.UI.WebControls.TextBox Login; protected System.Web.UI.WebControls.Label EmployeeID; ... EmployeeID.Text = Login.Text; %> <p><asp:label id="EmployeeID" runat="server" /></p>

Bad · ASP.NET

CVE ID	Title	CVSS	Severity	Published
CVE-2025-14149	Xpro Addons — 140+ Widgets for Elementor <= 1.4.24 - Authenticated (Contributor+) Stored Cross-Site Scripting via Image Scroller Widget box link — Xpro Addons — 140+ Widgets for Elementor	6.4	Medium	2026-02-27
CVE-2025-14040	Automotive Car Dealership Business WordPress Theme <= 13.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via Call to Action Fields — Automotive Car Dealership Business WordPress Theme	6.4	Medium	2026-02-27
CVE-2026-3302	SourceCodester Doctor Appointment System Sign Up register.php cross site scripting — Doctor Appointment System	4.3	Medium	2026-02-27
CVE-2026-28280	`osctrl-admin` has Stored Cross-Site Scripting (XSS) in On-Demand Query List — osctrl	6.1	Medium	2026-02-26
CVE-2026-28274	Initiative Vulnerable to Token Theft via Stored XSS in Document Uploads — initiative	8.7	High	2026-02-26
CVE-2026-27154	Discourse has XSS when editing a malicious post — discourse	5.4^AI	Medium ^AI	2026-02-26
CVE-2026-2680	Multiple vulnerabilities in A3factura software — A3factura	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-2679	Multiple vulnerabilities in A3factura software — A3factura	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-2678	Multiple vulnerabilities in A3factura software — A3factura	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-2677	Multiple vulnerabilities in A3factura software — A3factura	6.1^AI	Medium ^AI	2026-02-26
CVE-2025-14343	Reflected XSS in Dokuzsoft Technology's E-Commerce Product — E-Commerce Product	7.6	High	2026-02-26
CVE-2025-64999	Cross-site scripting in HTML logs of Synthetic Monitoring test services — Checkmk	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-28083	WordPress Flatsome theme <= 3.20.5 - Cross Site Scripting (XSS) vulnerability — Flatsome	6.5	Medium	2026-02-26
CVE-2026-1696	Missing security HTTP headers — PcVue	6.5^AI	Medium ^AI	2026-02-26
CVE-2026-1695	XSS vulnerability upon unsuccessful authentication — PcVue	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-27974	Audiobooksheld VUlnerable to Stored XSS in WrappingMarquee.js via Audiobook Metadata (Mobile App Audio Player) — audiobookshelf-app	4.8	Medium	2026-02-26
CVE-2026-27963	Audiobookshelf has Stored XSS in Tooltip.vue via Audiobook Metadata — audiobookshelf	4.8	Medium	2026-02-26
CVE-2026-27973	Audiobookshelf has Stored XSS in ItemSearchCard.vue via Audiobook Metadata (Search Results on Mobile App) — audiobookshelf	4.0	Medium	2026-02-26
CVE-2026-27970	Angular i18n vulnerable to Cross-Site Scripting (XSS) — angular	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-27948	Copyparty vulnerable to eflected cross-site scripting via setck parameter — copyparty	5.4	Medium	2026-02-26
CVE-2026-2499	Custom Logo <= 2.2 - Authenticated (Administrator+) Stored Cross-Site Scripting via Logo Path Setting — Custom Logo	4.4	Medium	2026-02-26
CVE-2026-2498	WP Social Meta <= 1.0.1 - Authenticated (Administrator+) Stored Cross-Site Scripting via Settings — WP Social Meta	4.4	Medium	2026-02-26
CVE-2026-2489	TP2WP Importer <= 1.1 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'Watched domains' Textarea — TP2WP Importer	4.4	Medium	2026-02-26
CVE-2026-2029	Livemesh Addons for Beaver Builder <= 3.9.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'title' and 'value' Shortcode Attributes — Livemesh Addons for Beaver Builder	6.4	Medium	2026-02-26
CVE-2026-2506	EM Cost Calculator <= 2.3.1 - Unauthenticated Stored Cross-Site Scripting via 'customer_name' — EM Cost Calculator	6.1	Medium	2026-02-26
CVE-2026-27902	Svelte Vulnerable to XSS via HTML Comment Injection in SSR Error Boundary Hydration Markers — svelte	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-27901	Svelte vulnerable to XSS during SSR with contenteditable `bind:innerText` and `bind:textContent` — svelte	6.1^AI	Medium ^AI	2026-02-26
CVE-2026-27616	Vikunja Vulnerable to Stored Cross-Site Scripting (XSS) via Unsanitized SVG Attachment Upload Leading to Token Exposure — vikunja	7.3	High	2026-02-25
CVE-2026-27116	Vikunja has Reflected HTML Injection via filter Parameter in Projects Module — vikunja	6.1	Medium	2026-02-25
CVE-2026-0752	Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab — GitLab	8.0	High	2026-02-25

Vulnerabilities classified as CWE-79 (在Web页面生成时对输入的转义处理不恰当(跨站脚本)) represent 23852 CVEs. The CWE taxonomy describes the weakness; review individual CVEs for product-specific impact.