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Common Weakness Enumeration

CWE-79

Allowed

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Abstraction: Base · Status: Stable

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.

69300 vulnerabilities reference this CWE, most recent first.

CVE-2026-86738 (GCVE-0-2026-86738)

Vulnerability from cvelistv5 – Published: 2026-09-08 15:14 – Updated: 2026-09-08 15:30
VLAI
Title
Snipe-IT before 8.7.0 CSS Injection via Custom CSS
Summary
Snipe-IT versions before 8.7.0 contain a CSS injection vulnerability in the Custom CSS field due to incomplete sanitization that reverses HTML encoding on greater-than and double-quote characters. Superusers can plant malicious CSS payloads using @import and url() references to exfiltrate CSRF tokens from other superusers via attribute-selector rules, enabling account takeover.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 15:30 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Impacted products
Vendor Product Version
grokability snipe-it Affected: 0 , < 8.7.0 (semver)
Unaffected: 8.7.0 (semver)
    cpe:2.3:a:snipeitapp:snipe-it:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-24 00:00
Show details on NVD website

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CVE-2026-86712 (GCVE-0-2026-86712)

Vulnerability from cvelistv5 – Published: 2026-09-08 11:23 – Updated: 2026-09-08 11:23
VLAI
Title
SiYuan before 3.8.2 Remote Code Execution via Clipboard
Summary
SiYuan before 3.8.2 trusts the attacker-writable text/siyuan clipboard MIME type and skips sanitization in the paste handler, allowing code execution in the Node-enabled desktop renderer. Attackers can craft malicious web pages that write to the clipboard, and when pasted into SiYuan, injected scripts execute with full Node.js access through the Electron main process.
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Impacted products
Vendor Product Version
siyuan-note siyuan Affected: 0 , < 3.8.2 (semver)
    cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-28 00:00
Credits
Show details on NVD website

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CVE-2026-86668 (GCVE-0-2026-86668)

Vulnerability from cvelistv5 – Published: 2026-09-08 16:45 – Updated: 2026-09-08 16:45
VLAI
Title
aircheng-org iWebShop-5 pic.php uploadFile cross site scripting
Summary
A security vulnerability has been detected in aircheng-org iWebShop-5 up to 5.15. The impacted element is the function uploadFile of the file controllers/pic.php. Such manipulation of the argument outerSrc/selectPhoto leads to cross site scripting. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.
CWE
References
URL Tags
https://vuldb.com/vuln/399759 vdb-entrytechnical-description
https://vuldb.com/vuln/399759/cti signaturepermissions-required
https://vuldb.com/cve/CVE-2026-86668 third-party-advisory
https://vuldb.com/submit/908926 third-party-advisory
https://github.com/aircheng-org/iWebShop-5/issues/4 exploitissue-tracking
https://github.com/aircheng-org/iWebShop-5/ product
Impacted products
Vendor Product Version
aircheng-org iWebShop-5 Affected: 5.0
Affected: 5.1
Affected: 5.2
Affected: 5.3
Affected: 5.4
Affected: 5.5
Affected: 5.6
Affected: 5.7
Affected: 5.8
Affected: 5.9
Affected: 5.10
Affected: 5.11
Affected: 5.12
Affected: 5.13
Affected: 5.14
Affected: 5.15
    cpe:2.3:a:aircheng-org:iwebshop-5:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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CVE-2026-86644 (GCVE-0-2026-86644)

Vulnerability from cvelistv5 – Published: 2026-09-08 13:30 – Updated: 2026-09-08 15:42 X_Open Source
VLAI
Title
star7th showdoc API Page Save Endpoint editormd.js cross site scripting
Summary
A vulnerability was determined in star7th showdoc up to 3.9.1. This vulnerability affects unknown code of the file web_src/public/editor.md/editormd.js of the component API Page Save Endpoint. Executing a manipulation can lead to cross site scripting. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 3.9.2 is able to resolve this issue. This patch is called a8ea1520850b4242f395247f72e87e597506cef0. Upgrading the affected component is recommended. The vendor confirms: "The fix [...] sets Mermaid `securityLevel` to `strict`, disables `htmlLabels`, and sanitizes rendered SVG with DOMPurify."
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 15:42 UTC
CWE
Impacted products
Vendor Product Version
star7th showdoc Affected: 3.9.0
Affected: 3.9.1
Unaffected: 3.9.2
    cpe:2.3:a:showdoc:showdoc:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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CVE-2026-86550 (GCVE-0-2026-86550)

Vulnerability from cvelistv5 – Published: 2026-09-08 08:14 – Updated: 2026-09-08 12:24
VLAI
Title
UXSS vulnerability in ZTE browser products
Summary
NuBrowser lacks protocol whitelist validation for the S.browser_fallback_url field of intent://, allowing attackers to inject javascript: URLs via 302 redirects. This results in a universal cross‑site scripting (UXSS) vulnerability that enables script execution within the origin of arbitrary websites.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 12:23 UTC
CWE
  • CWE-79 - Improper neutralization of input during web page generation ('cross-site scripting')
Assigner
Impacted products
Vendor Product Version
ZTE NebulaOS Affected: Versions prior to Browser V1.6.8
Create a notification for this product.
Credits
Show details on NVD website

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CVE-2026-86440 (GCVE-0-2026-86440)

Vulnerability from cvelistv5 – Published: 2026-09-07 12:35 – Updated: 2026-09-08 14:51
VLAI
Title
MISP Dashboard Button Widget Allows Stored XSS via Unsafe javascript: and Backslash URLs
Summary
Affected versions of MISP insufficiently validate URLs used by dashboard widgets, particularly the Button widget. The widget's URL is stored configuration controlled by a user. The previous renderer considered a URL safe if it appeared relative or if its parsed hostname matched the configured MISP hostname. That logic failed to reject dangerous schemes and URL forms that browsers normalize differently from PHP's URL parsing. As a result, values such as javascript: URLs or backslash-based authority forms could reach the generated anchor's href and execute script or navigate to an attacker-controlled origin when another user interacted with the widget. The upstream commit describes the issue as: “javascript: and backslash URLs reached the href (stored XSS)”. The fix routes widget URLs through a shared DashboardURLValidator, rejects dangerous schemes, raw backslashes, control characters, and unauthorized absolute origins, and validates the URL both in the widget handler and renderer. Version affected: ≤2.5.45
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 14:51 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')
  • CWE-20 - Improper Input Validation
References
Impacted products
Vendor Product Version
MISP MISP Affected: 0 , ≤ 2.5.45 (semver)
Create a notification for this product.
Show details on NVD website

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CVE-2026-86431 (GCVE-0-2026-86431)

Vulnerability from cvelistv5 – Published: 2026-09-07 12:53 – Updated: 2026-09-08 13:33
VLAI
Title
commonmark before 2.9.1 XSS via AttributesExtension form feed bypass
Summary
league/commonmark (thephpleague/commonmark) versions >= 2.7.0 and < 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte (e.g. {\x0Conclick="alert(1)"}) bypasses the AttributesHelper::filterAttributes() 'on*' event-handler filter because PHP's trim() does not strip U+000C, causing the attribute to be written verbatim into the output where browsers parse it as a genuine event handler. The same prefix also defeats the allow_unsafe_links check, allowing javascript: URIs through href/src attributes even when allow_unsafe_links is false. Exploitation requires processing untrusted Markdown with the AttributesExtension enabled; the injected script executes when the rendered HTML is viewed. Fixed in 2.9.1.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 13:30 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Impacted products
Vendor Product Version
thephpleague commonmark Affected: 2.7.0 , < 2.9.1 (semver)
Unaffected: 2.9.1 (semver)
    cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-09 00:00
Show details on NVD website

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CVE-2026-86301 (GCVE-0-2026-86301)

Vulnerability from cvelistv5 – Published: 2026-09-07 11:45 – Updated: 2026-09-08 14:06 X_Freeware
VLAI
Title
code-projects Hospital Information System Patient Management editPatient.php cross site scripting
Summary
A vulnerability has been found in code-projects Hospital Information System 1.0. Affected is an unknown function of the file /HIS/src/patients/editPatient.php of the component Patient Management. Such manipulation of the argument ID leads to cross site scripting. The attack may be launched remotely. The exploit has been disclosed to the public and may be used.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 14:05 UTC
CWE
References
Impacted products
Vendor Product Version
code-projects Hospital Information System Affected: 1.0
    cpe:2.3:a:code-projects:hospital_information_system:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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CVE-2026-86294 (GCVE-0-2026-86294)

Vulnerability from cvelistv5 – Published: 2026-09-07 10:00 – Updated: 2026-09-07 10:00 X_Freeware
VLAI
Title
SourceCodester Simple Traffic Offense System Settings Update Endpoint save-settings.php cross site scripting
Summary
A vulnerability has been found in SourceCodester Simple Traffic Offense System 1.0. Affected by this issue is some unknown functionality of the file save-settings.php of the component Settings Update Endpoint. The manipulation of the argument site_name/site_desc leads to cross site scripting. Remote exploitation of the attack is possible. The exploit has been disclosed to the public and may be used.
CWE
References
URL Tags
https://vuldb.com/vuln/399456 vdb-entrytechnical-description
https://vuldb.com/vuln/399456/cti signaturepermissions-required
https://vuldb.com/cve/CVE-2026-86294 third-party-advisory
https://vuldb.com/submit/906279 third-party-advisory
https://github.com/tan1540684326-QAQ/cve/issues/3 exploitissue-tracking
https://www.sourcecodester.com/ product
Impacted products
Vendor Product Version
SourceCodester Simple Traffic Offense System Affected: 1.0
    cpe:2.3:a:sourcecodester:simple_traffic_offense_system:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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CVE-2026-86278 (GCVE-0-2026-86278)

Vulnerability from cvelistv5 – Published: 2026-09-07 06:45 – Updated: 2026-09-08 14:33 X_Freeware
VLAI
Title
SourceCodester Syllabus-Aligned Learning Management & Examination System manage_subjects.php cross site scripting
Summary
A vulnerability was found in SourceCodester Syllabus-Aligned Learning Management & Examination System 1.0. The affected element is an unknown function of the file manage_subjects.php. The manipulation of the argument msg/title/content results in cross site scripting. The attack may be performed from remote. The exploit has been made public and could be used.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 14:28 UTC
CWE
References
Impacted products
Vendor Product Version
SourceCodester Syllabus-Aligned Learning Management & Examination System Affected: 1.0
    cpe:2.3:a:sourcecodester:syllabus-aligned_learning_management_examination_system:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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Mitigation MIT-4
Architecture and Design

Strategy: Libraries or Frameworks

  • 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.
Mitigation
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 encoding strategies.
  • For any data that will be output to another web page, especially any data that was received from external inputs, use the appropriate encoding on all non-alphanumeric characters.
  • Parts of the same output document may require different encodings, which will vary depending on whether the output is in the:
  • etc. Note that HTML Entity Encoding is only appropriate for the HTML body.
  • Consult the XSS Prevention Cheat Sheet [REF-724] for more details on the types of encoding and escaping that are needed.
  • HTML body
  • Element attributes (such as src="XYZ")
  • URIs
  • JavaScript sections
  • Cascading Style Sheets and style property
Mitigation MIT-6
Architecture and Design Implementation

Strategy: Attack Surface Reduction

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 through API calls.

Mitigation MIT-15
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.

Mitigation MIT-27
Architecture and Design

Strategy: Parameterization

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.

Mitigation MIT-30.1
Implementation

Strategy: Output Encoding

  • Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
  • The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.
Mitigation MIT-43
Implementation

With Struts, write all data from form beans with the bean's filter attribute set to true.

Mitigation MIT-31
Implementation

Strategy: Attack Surface Reduction

To help mitigate XSS attacks against the user's session cookie, set the session cookie to be HttpOnly. In browsers that support the HttpOnly feature (such as more recent versions of Internet Explorer and Firefox), this attribute can prevent the user's session cookie from being accessible to malicious client-side scripts that use document.cookie. This is not a complete solution, since HttpOnly is not supported by all browsers. More importantly, XmlHttpRequest and other powerful browser technologies provide read access to HTTP headers, including the Set-Cookie header in which the HttpOnly flag is set.

Mitigation MIT-5
Implementation

Strategy: Input Validation

  • Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
  • When dynamically constructing web pages, use stringent allowlists that limit the character set based on the expected value of the parameter in the request. All input should be validated and cleansed, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. It is common to see data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended.
  • Note that proper output encoding, escaping, and quoting is the most effective solution for preventing XSS, although input validation may provide some defense-in-depth. This is because it effectively limits what will appear in output. Input validation will not always prevent XSS, especially if you are required to support free-form text fields that could contain arbitrary characters. For example, in a chat application, the heart emoticon ("<3") would likely pass the validation step, since it is commonly used. However, it cannot be directly inserted into the web page because it contains the "<" character, which would need to be escaped or otherwise handled. In this case, stripping the "<" might reduce the risk of XSS, but it would produce incorrect behavior because the emoticon would not be recorded. This might seem to be a minor inconvenience, but it would be more important in a mathematical forum that wants to represent inequalities.
  • Even if you make a mistake in your validation (such as forgetting one out of 100 input fields), appropriate encoding is still likely to protect you from injection-based attacks. As long as it is not done in isolation, input validation is still a useful technique, since it may significantly reduce your attack surface, allow you to detect some attacks, and provide other security benefits that proper encoding does not address.
  • Ensure that you perform input validation at well-defined interfaces within the application. This will help protect the application even if a component is reused or moved elsewhere.
Mitigation MIT-21
Architecture and Design

Strategy: Enforcement by Conversion

When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.

Mitigation MIT-29
Operation

Strategy: Firewall

Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].

Mitigation MIT-16
Operation Implementation

Strategy: Environment Hardening

When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.

CAPEC-209: XSS Using MIME Type Mismatch

An adversary creates a file with scripting content but where the specified MIME type of the file is such that scripting is not expected. The adversary tricks the victim into accessing a URL that responds with the script file. Some browsers will detect that the specified MIME type of the file does not match the actual type of its content and will automatically switch to using an interpreter for the real content type. If the browser does not invoke script filters before doing this, the adversary's script may run on the target unsanitized, possibly revealing the victim's cookies or executing arbitrary script in their browser.

CAPEC-588: DOM-Based XSS

This type of attack is a form of Cross-Site Scripting (XSS) where a malicious script is inserted into the client-side HTML being parsed by a web browser. Content served by a vulnerable web application includes script code used to manipulate the Document Object Model (DOM). This script code either does not properly validate input, or does not perform proper output encoding, thus creating an opportunity for an adversary to inject a malicious script launch a XSS attack. A key distinction between other XSS attacks and DOM-based attacks is that in other XSS attacks, the malicious script runs when the vulnerable web page is initially loaded, while a DOM-based attack executes sometime after the page loads. Another distinction of DOM-based attacks is that in some cases, the malicious script is never sent to the vulnerable web server at all. An attack like this is guaranteed to bypass any server-side filtering attempts to protect users.

CAPEC-591: Reflected XSS

This type of attack is a form of Cross-Site Scripting (XSS) where a malicious script is "reflected" off a vulnerable web application and then executed by a victim's browser. The process starts with an adversary delivering a malicious script to a victim and convincing the victim to send the script to the vulnerable web application.

CAPEC-592: Stored XSS

An adversary utilizes a form of Cross-site Scripting (XSS) where a malicious script is persistently "stored" within the data storage of a vulnerable web application as valid input.

CAPEC-63: Cross-Site Scripting (XSS)

An adversary embeds malicious scripts in content that will be served to web browsers. The goal of the attack is for the target software, the client-side browser, to execute the script with the users' privilege level. An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute code and scripts. Web browsers, for example, have some simple security controls in place, but if a remote attacker is allowed to execute scripts (through injecting them in to user-generated content like bulletin boards) then these controls may be bypassed. Further, these attacks are very difficult for an end user to detect.

CAPEC-85: AJAX Footprinting

This attack utilizes the frequent client-server roundtrips in Ajax conversation to scan a system. While Ajax does not open up new vulnerabilities per se, it does optimize them from an attacker point of view. A common first step for an attacker is to footprint the target environment to understand what attacks will work. Since footprinting relies on enumeration, the conversational pattern of rapid, multiple requests and responses that are typical in Ajax applications enable an attacker to look for many vulnerabilities, well-known ports, network locations and so on. The knowledge gained through Ajax fingerprinting can be used to support other attacks, such as XSS.