# CVE-2026-93504: SveltyCMS User Attribute Update improper access control

Source: https://junglewise.ai/threats/cve-2026-93504-sveltycms-user-attribute-update-improper-access-control  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-18. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-93504 · Severity: medium · CVSS 6.3 · Published 2026-09-18

SveltyCMS is a headless content management system used by developers to manage website content. The User Attribute Update API endpoint in version 0.0.6 contains an access control flaw that allows attackers to modify user attributes and potentially escalate privileges. This could result in unauthorized account takeovers or administrative access gains.

Technologies: [SveltyCMS](https://junglewise.ai/threats/technologies/sveltycms). Vendors: [SveltyCMS](https://junglewise.ai/threats/vendors/sveltycms).

## Quick answers

**Is CVE-2026-93504 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-93504 being exploited in the wild.

**How severe is CVE-2026-93504?** Medium severity, with a CVSS score of 6.3, published 18 September 2026.

**Which products and versions are affected?** SveltyCMS 0.0.6.

**Is there a fix for CVE-2026-93504?** A patch was published on 2026-08-07: Patch commit 05b4f9efeb79e9d72a693232334d7529687f896f Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-93504 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-93504?** Check whether you run SveltyCMS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the User Attribute Update Endpoint (src/routes/api/[...path]/+server.ts) and involves improper access controls on user attribute modifications. The flaw is classified as a privilege escalation issue (related to CWE-269) where the endpoint fails to properly restrict modification of sensitive user fields such as `role`, `isAdmin`, and other privileged attributes. The vulnerability is remotely exploitable without requiring prior authentication or special preconditions. Patch 05b4f9efeb79e9d72a693232334d7529687f896f implements `stripPrivilegedUserFields()` policy to drop privileged attributes from client payloads at both the handler and adapter layers, along with fail-closed privilege dropping mechanisms.

## Affected products

- SveltyCMS SveltyCMS 0.0.6

## Timeline

- 2026-09-18: disclosed
- 2026-08-07: patched: Patch commit 05b4f9efeb79e9d72a693232334d7529687f896f

## References

- [https://github.com/SveltyCMS/SveltyCMS/](https://github.com/SveltyCMS/SveltyCMS/)
- [https://github.com/SveltyCMS/SveltyCMS/commit/05b4f9efeb79e9d72a693232334d7529687f896f](https://github.com/SveltyCMS/SveltyCMS/commit/05b4f9efeb79e9d72a693232334d7529687f896f)

## Related threats

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