# CVE-2026-70552: MaxSite CMS 109.5 Unauthenticated AJAX Dispatcher Bypass via ajax.php

> Unauthenticated attackers can bypass authentication in MaxSite CMS to access admin-only AJAX endpoints, allowing unauthorized modification of data and privileged actions.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 Aug 2026
- **Updated:** 24 Sep 2026
- **Also known as:** GHSA-r998-r395-678g

## What is CVE-2026-70552?

CVE-2026-70552 is a critical authentication bypass vulnerability in MaxSite CMS, published on 4 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

MaxSite CMS 109.5 and earlier contains an authentication bypass vulnerability in the AJAX dispatcher that allows unauthenticated attackers to access admin-gated endpoints by supplying any X-Requested-With header and requesting a base64-encoded path resolving to any *-ajax.php file in the codebase. Attackers can exploit this dispatcher bypass to reach privileged plugin endpoints without credentials, enabling actions such as manipulating poll states and vote counts, and amplifying the impact of any dangerous operation performed by admin-only ajax files across the plugin tree.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2026-70552?


## How do I fix CVE-2026-70552?

No fix has been published for CVE-2026-70552 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-70552 being exploited?

There is no known exploitation of CVE-2026-70552 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-70552 and fix it if it is affected.

What it is: CVE-2026-70552 is a critical authentication bypass vulnerability in MaxSite CMS, published on 4 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-70552 in the wild and no public exploit code.

Affected product: MaxSite CMS. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-70552/ (Markdown: https://insights.sbomify.com/CVE-2026-70552/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-70552
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-70552
- OSV: https://osv.dev/vulnerability/CVE-2026-70552

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-70552/
Summaries are generated and may contain mistakes; the official description above is the record.