Add 829 documentation for browser based DAST

- Adds 829.1 check documentation
- Updates index page to link to 829.1
- Adds 829.2 check documentation
- Updates index page to link to 829.2

doc/user/application_security/dast/checks/829.1.md

+---
+stage: Secure
+group: Dynamic Analysis
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Inclusion of Functionality from Untrusted Control Sphere
+
+## Description
+
+JavaScript or CSS source files are included from third party domains without
+[Sub-Resource Integrity (SRI)](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity).
+If an attacker were to compromise the sites hosting these third party resources, they could inject malicious
+script or CSS data in an attempt to compromise users of your application. However, if SRI was applied and an
+attacker attempted to modify the contents of the script, the browser would not load the script and your
+applications users would be protected from the malicious alterations.
+
+## Remediation
+
+All identified resources should be sourced from the same domain as the target application. If this is not
+possible, it is strongly recommended that all `script` tags that implement `src` values, or `link` tags
+that implement the `href` values include Sub-Resource Integrity. To generate SRI integrity values the
+[srihash](https://www.srihash.org/) tool can be used, or by running one of the following commands:
+
+- `cat FILENAME.js | openssl dgst -sha384 -binary | openssl base64 -A`
+- `shasum -b -a 384 FILENAME.js | awk '{ print $1 }' | xxd -r -p | base64`
+
+The output of these tools must be added as additional attributes, in particular: `integrity` and either
+`crossorigin=anonymous` or `crossorigin=use-credentials`.
+An example of a valid SRI protected script tag can be found below:
+
+```html
+<script src="https://example.com/example-framework.js"
+    integrity="sha384-oqVuAfXRKap7fdgcCY5uykM6+R9GqQ8K/uxy9rx7HNQlGYl1kPzQho1wx4JwY8wC"
+    crossorigin="anonymous"></script>
+```
+
+## Details
+
+| ID | Aggregated | CWE | Type | Risk |
+|:---|:--------|:--------|:--------|:--------|
+| 829.1 | true | 829 | Passive | Low |
+
+## Links
+
+- [OWASP](https://cheatsheetseries.owasp.org/cheatsheets/Third_Party_Javascript_Management_Cheat_Sheet.html#subresource-integrity)
+- [CWE](https://cwe.mitre.org/data/definitions/829.html)
+- [MDN](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity)

doc/user/application_security/dast/checks/829.2.md

+---
+stage: Secure
+group: Dynamic Analysis
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Invalid Sub-Resource Integrity values detected
+
+## Description
+
+JavaScript or CSS source files were found to contain invalid
+[Sub-Resource Integrity (SRI)](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity)
+`integrity` values or a missing `crossorigin` value. These scripts or links should be investigated to
+ensure they have not been maliciously altered. If in doubt, contact the owner of the scripts or replace
+them with known good versions.
+
+## Remediation
+
+All identified resources should be sourced from the same domain as the target application. If this is not
+possible, it is strongly recommended that all `script` tags that implement `src` values, or `link` tags
+that implement the `href` values include Sub-Resource Integrity. To generate SRI integrity values the
+[srihash](https://www.srihash.org/) tool can be used, or by running one of the following commands:
+
+- `cat FILENAME.js | openssl dgst -sha384 -binary | openssl base64 -A`
+- `shasum -b -a 384 FILENAME.js | awk '{ print $1 }' | xxd -r -p | base64`
+
+The output of these tools must be added as additional attributes, in particular: `integrity` and either
+`crossorigin=anonymous` or `crossorigin=use-credentials`.
+An example of a valid SRI protected script tag can be found below:
+
+```html
+<script src="https://example.com/example-framework.js"
+    integrity="sha384-oqVuAfXRKap7fdgcCY5uykM6+R9GqQ8K/uxy9rx7HNQlGYl1kPzQho1wx4JwY8wC"
+    crossorigin="anonymous"></script>
+```
+
+## Details
+
+| ID | Aggregated | CWE | Type | Risk |
+|:---|:--------|:--------|:--------|:--------|
+| 829.2 | true | 829 | Passive | Medium |
+
+## Links
+
+- [OWASP](https://cheatsheetseries.owasp.org/cheatsheets/Third_Party_Javascript_Management_Cheat_Sheet.html#subresource-integrity)
+- [CWE](https://cwe.mitre.org/data/definitions/829.html)
+- [MDN](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity)

doc/user/application_security/dast/checks/index.md

@@ -24,3 +24,5 @@ The [DAST browser-based crawler](../browser_based.md) provides a number of vulne
 | [598.3](598.3.md) | Use of GET request method with sensitive query strings (Authorization header details) | Medium | Passive |
 | [614.1](614.1.md) | Sensitive cookie without Secure attribute | Low | Passive |
 | [693.1](693.1.md) | Missing X-Content-Type-Options: nosniff | Low | Passive |
+| [829.1](829.1.md) | Inclusion of Functionality from Untrusted Control Sphere | Low | Passive |
+| [829.2](829.2.md) | Invalid Sub-Resource Integrity values detected | Medium | Passive |