Common Weakness Enumeration
CWE-79
AllowedImproper 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.
66728 vulnerabilities reference this CWE, most recent first.
CVE-2026-53693 (GCVE-0-2026-53693)
Vulnerability from cvelistv5 – Published: 2026-06-10 14:34 – Updated: 2026-06-10 16:15
VLAI
EPSS
VEX
Title
MISP BSimVis stored cross-site scripting in tag and cluster rendering paths via unescaped tag metadata and UI labels
Summary
A stored cross-site scripting vulnerability existed in MISP BSimVis tag rendering code. Several client-side rendering paths interpolated tag names, collection names, entity identifiers, cluster names, and tag metadata directly into HTML, HTML attributes, inline JavaScript event handlers, and CSS style values without context-appropriate escaping. The patch adds shared escaping helpers for HTML, attributes, JavaScript strings, and CSS color validation, then applies them across tag badges, tooltips, context menus, cluster cards, autocomplete suggestions, and dynamically inserted tag cards.
An attacker able to create or influence stored tag or metadata values could inject a crafted payload that is later rendered in another user’s browser. Successful exploitation could execute arbitrary JavaScript in the victim’s session when they view affected BSimVis pages, potentially allowing the attacker to perform actions as the victim, read data available to the victim, or alter displayed application content.
This issue affects MISP bsimvis: through v0.2.0.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/MISP/bsimvis/commit/7bcd2c2e27… | patch |
Credits
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CVE-2026-53662 (GCVE-0-2026-53662)
Vulnerability from cvelistv5 – Published: 2026-06-23 17:36 – Updated: 2026-06-23 18:32
VLAI
EPSS
VEX
Title
immich: One-click account takeover via XSS in login page continue redirect
Summary
immich is a high performance self-hosted photo and video management solution. From commit 4ffa26c9 until 4eb1003, a reflected cross-site scripting (XSS) vulnerability on the /auth/login page allows an attacker to fully compromise any authenticated user's account with a single link click. The continue query parameter is read from the URL and passed to SvelteKit's redirect() without any scheme or origin validation, allowing attacker-controlled JavaScript to execute inside Immich's origin. The payload then uses the victim's existing session to mint an all-permission API key on their account, leading to persistent account takeover. This vulnerability is fixed in commit 4eb1003.
Severity
9.6 (Critical)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/immich-app/immich/security/adv… | x_refsource_CONFIRM |
| https://github.com/immich-app/immich/commit/4eb10… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| immich-app | immich |
Affected:
>= main@4ffa26c9, < main@4eb1003
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CVE-2026-53641 (GCVE-0-2026-53641)
Vulnerability from cvelistv5 – Published: 2026-07-06 22:36 – Updated: 2026-07-08 19:41
VLAI
EPSS
VEX
Title
FOSSBilling has stored XSS in client email views via unescaped content in JavaScript template literal
Summary
FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have a stored cross-site scripting (XSS) vulnerability in the client-facing email history views of FOSSBilling. Email HTML content (`content_html`) is rendered into a JavaScript template literal using the `|raw` filter, bypassing all output escaping. An attacker with admin access can inject malicious JavaScript payloads into email content that execute in the browser of any client who views their email history. Version 0.8.0 contains a fix. Some workarounds are available. Restrict admin account access, audit email content in the database for suspicious payloads, and/or monitor client accounts for unusual activity.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/FOSSBilling/FOSSBilling/securi… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| FOSSBilling | FOSSBilling |
Affected:
>= 0.6.0, < 0.8.0
|
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CVE-2026-53608 (GCVE-0-2026-53608)
Vulnerability from cvelistv5 – Published: 2026-06-12 20:57 – Updated: 2026-06-15 17:49
VLAI
EPSS
VEX
Title
@apostrophecms/seo Vulnerable to Stored XSS via Unsanitized Google Analytics / GTM ID Injected into Script Tag
Summary
ApostropheCMS is an open-source Node.js content management system. Versions up to and including 1.4.2 of the `@apostrophecms/seo` package injects the Google Analytics Tracking ID (`seoGoogleTrackingId`) and Google Tag Manager ID (`seoGoogleTagManager`) directly into `<script>` tag bodies using JavaScript template literals without any sanitization or validation. Any user with editor-level access (the default role for content managers) can set these fields to a malicious value, resulting in stored XSS that executes on every page for every visitor of the site. As of time of publication, no known patched versions are available.
Severity
8.7 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/apostrophecms/apostrophe/secur… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| apostrophecms | @apostrophecms/seo |
Affected:
<= 1.4.2
|
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CVE-2026-53606 (GCVE-0-2026-53606)
Vulnerability from cvelistv5 – Published: 2026-06-12 20:50 – Updated: 2026-06-15 17:54
VLAI
EPSS
VEX
Title
sanitize-html has an incomplete URI scheme validation that allows javascript: URIs through action, formaction, data, poster, and background attributes
Summary
ApostropheCMS is an open-source Node.js content management system, and sanitize-html provides a simple HTML sanitizer with a clear API. Versions of sanitize-html prior to 2.17.5 use `allowedSchemesAppliedToAttributes` (default: `['href', 'src', 'cite']`) to gate the `naughtyHref()` function that blocks dangerous URI schemes like `javascript:` and `vbscript:`. The HTML specification defines 10+ attributes that accept URIs (`action`, `formaction`, `data`, `poster`, `background`, `ping`, `xlink:href`, `dynsrc`, `lowsrc`), but none of these are included in the default gate list. When a developer allows any of these attributes in their configuration, `javascript:` URIs pass through completely unmodified, enabling XSS. Version 2.17.5 patches the issue.
Severity
5.4 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/apostrophecms/apostrophe/secur… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| apostrophecms | sanitize-html |
Affected:
< 2.17.5
|
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CVE-2026-53568 (GCVE-0-2026-53568)
Vulnerability from cvelistv5 – Published: 2026-06-12 14:45 – Updated: 2026-06-12 16:08
VLAI
EPSS
VEX
Title
Frappe: Stored XSS in Frappe Report/List View via 'set_link_title_field_value'
Summary
Frappe is a full-stack web application framework. Prior to versions 15.107.2 and 16.17.4, there is a stored XSS vulnerablity in Frappe Report/List View. This issue has been patched in versions 15.107.2 and 16.17.4.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/frappe/frappe/security/advisor… | x_refsource_CONFIRM |
Impacted products
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CVE-2026-53473 (GCVE-0-2026-53473)
Vulnerability from cvelistv5 – Published: 2026-06-10 13:55 – Updated: 2026-06-10 15:46
VLAI
EPSS
VEX
Title
Migration-planner-ui-app: stored xss via javascript: url in agent credential link
Summary
A flaw was found in migration-planner-ui-app. An attacker can register a malicious discovery agent with a specially crafted credentialUrl containing JavaScript code. When an organizational user clicks this link in the user interface, the embedded malicious code executes within the user's browser session. This cross-site scripting (XSS) vulnerability allows the attacker to compromise the victim's Red Hat Single Sign-On (SSO) session, potentially leading to unauthorized cross-tenant data access and API actions.
Severity
7.3 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-53473 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2487107 | issue-trackingx_refsource_REDHAT |
| https://github.com/kubev2v/migration-planner-ui-a… |
Date Public
2026-06-07 00:00
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CVE-2026-53427 (GCVE-0-2026-53427)
Vulnerability from cvelistv5 – Published: 2026-06-29 18:50 – Updated: 2026-06-30 04:37
VLAI
EPSS
VEX
Title
Cross-site scripting in MDEx via unescaped highlight_lines_class code-fence attribute
Summary
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in leandrocp MDEx allows stored or reflected cross-site scripting via attacker-controlled Markdown.
When syntax highlighting and full info-string forwarding (render: [full_info_string: true]) are enabled, the Lumis adapter copies the value of a code fence's highlight_lines_class info-string attribute, unescaped, into the class attribute of every rendered line. comrak_nif::lumis_adapter::LumisAdapter::parse_custom_attributes in native/comrak_nif/src/lumis_adapter.rs shlex-parses the info string and stores each key=value pair verbatim, highlight_lines_config pulls highlight_lines_class into the per-line class value, and write_highlighted interpolates that value directly into the class attribute of the per-line <div>. A single-quoted shell token preserves an inner double quote through shlex parsing, so a value such as '"><script>alert(1)</script>' terminates the class attribute early and the markup that follows is emitted as live HTML.
An attacker who can submit Markdown (through comments, posts, wiki pages, documentation, or any user-generated content) can inject arbitrary HTML and JavaScript that runs in the browser of every user who views the rendered output, enabling session theft, account takeover, and other client-side attacks. No authentication or special privileges are required.
The vulnerable native code originally shipped inside mdex (in native/comrak_nif/src/lumis_adapter.rs) and was later extracted into the separate mdex_native package (native/mdex_native_nif/src/lumis_adapter.rs), where it remains unpatched.
This issue affects mdex from 0.11.3 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/leandrocp/mdex_native/security… | vendor-advisoryrelated |
| https://cna.erlef.org/cves/CVE-2026-53427.html | related |
| https://osv.dev/vulnerability/EEF-CVE-2026-53427 | related |
| https://github.com/leandrocp/mdex_native/commit/7… | patch |
Impacted products
4 products
| Vendor | Product | Version | |
|---|---|---|---|
| leandrocp | mdex |
Affected:
0.11.3 , < 0.12.3
(semver)
cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex |
Affected:
0d7ffc84ea742e1daf666426814e5bb6d0499433 , < 6ed94d905f97af188323f042698ae841c02293b4
(git)
cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex_native |
Affected:
0.1.0 , < 0.2.3
(semver)
cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex_native |
Affected:
956528c5e31746253347029e810a969ab916fd27 , < 798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3
(git)
cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:* |
Credits
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CVE-2026-52838 (GCVE-0-2026-52838)
Vulnerability from cvelistv5 – Published: 2026-07-14 15:07 – Updated: 2026-07-14 16:26
VLAI
EPSS
VEX
Title
Easy!Appointments disable_booking_message rendered as raw HTML on public booking page — Stored XSS
Summary
Easy!Appointments is a self hosted appointment scheduler. Versions prior to 1.6.0 allow administrators to define a custom "booking disabled" message through the booking settings page. That value is stored in the `disable_booking_message` setting via a rich-text editor and later passed directly to the public `booking_message` view without escaping or sanitization. An authenticated administrator can store HTML or JavaScript in this field, enable disabled-booking mode, and trigger stored XSS in every unauthenticated visitor who opens the public booking page. Version 1.6.0 fixes the issue.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/alextselegidis/easyappointment… | x_refsource_CONFIRM |
| https://github.com/alextselegidis/easyappointment… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| alextselegidis | easyappointments |
Affected:
< 1.6.0
|
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CVE-2026-52807 (GCVE-0-2026-52807)
Vulnerability from cvelistv5 – Published: 2026-06-24 20:25 – Updated: 2026-06-25 15:37
VLAI
EPSS
VEX
Title
Gogs: DOM-based XSS via Milestone Name on New Issue Page
Summary
Gogs is an open source self-hosted Git service. Prior to 0.14.3, in new_form.tmpl, milestone names are rendered with Go's default auto-escaping ({{.Name}}), which converts < to < etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the decoded original payload. Semantic UI 2.4.2's dropdown component has preserveHTML: true as the default setting. When a user selects a dropdown item, the internal set.text() method calls jQuery's .html() with the item's text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI's preserveHTML behavior. This vulnerability is fixed in 0.14.3.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/gogs/gogs/security/advisories/… | x_refsource_CONFIRM |
| https://github.com/gogs/gogs/pull/8325 | x_refsource_MISC |
| https://github.com/gogs/gogs/commit/573eacdc65864… | x_refsource_MISC |
| https://github.com/gogs/gogs/releases/tag/v0.14.3 | x_refsource_MISC |
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},
{
"name": "https://github.com/gogs/gogs/pull/8325",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/gogs/gogs/pull/8325"
},
{
"name": "https://github.com/gogs/gogs/commit/573eacdc658641487f8ad883da96b29ec8e2852d",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/gogs/gogs/commit/573eacdc658641487f8ad883da96b29ec8e2852d"
},
{
"name": "https://github.com/gogs/gogs/releases/tag/v0.14.3",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/gogs/gogs/releases/tag/v0.14.3"
}
],
"source": {
"advisory": "GHSA-vcm5-gvmp-78mp",
"discovery": "UNKNOWN"
},
"title": "Gogs: DOM-based XSS via Milestone Name on New Issue Page"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-52807",
"datePublished": "2026-06-24T20:25:49.230Z",
"dateReserved": "2026-06-08T18:02:19.731Z",
"dateUpdated": "2026-06-25T15:37:35.956Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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.