CVE-2026-81852 AshAdmin ships a hardcoded CSP nonce, allowing nonce-based CSP bypass
AshAdmin uses a hardcoded CSP nonce, allowing attackers to bypass Content-Security-Policy protections and execute inline scripts on admin pages.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-81852?
CVE-2026-81852 is a low-severity vulnerability in ash-project ash_admin, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Use of Insufficiently Random Values vulnerability in ash-project ash_admin ships a hardcoded, publicly known CSP nonce, defeating nonce-based Content-Security-Policy protection.
When mounted without :csp_nonce_assign_key, AshAdmin.Router.ash_admin/2 defaulted the img, style, and script nonces to the literal constant ash_admin-Ed55GFnX, which AshAdmin.Layouts wrote verbatim into the nonce attribute of its inline <style> and <script> tags on every response. The value is a compile-time constant published in the repository and is never rotated per request. If an application's CSP script-src allow-lists that documented default, any HTML-injection sink on an admin page can reuse the known nonce to run inline scripts the policy was meant to block. The fix generates a fresh random nonce per request.
This issue affects ash_admin: from 0.10.8 before 1.3.1.
Weakness: CWE-330
Which versions are affected by CVE-2026-81852?
1 open source package ship an affected version, including ash_admin.
| Package | Affected | Fixed in |
|---|---|---|
ash_admin Hex | From 0.10.8 | 1.3.1 |
How do I fix CVE-2026-81852?
Upgrade ash_admin to 1.3.1 or later.
Is CVE-2026-81852 being exploited?
There is no known exploitation of CVE-2026-81852 in the wild and no public exploit code.
Sources
Also known as EEF-CVE-2026-81852, GHSA-whfj-rrrp-j597.