# CVE-2026-26335: Calero VeraSMART < 2022 R1 Static IIS Machine Keys Enable ViewState RCE

> Attackers with static machine keys can craft ViewState payloads to trigger deserialization and achieve remote code execution on VeraSMART servers.

- **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:** 13 Feb 2026
- **Updated:** 14 Jul 2026
- **Also known as:** GHSA-pw8j-97jq-cw6g

## What is CVE-2026-26335?

CVE-2026-26335 is a critical unsafe deserialization vulnerability in Calero VeraSMART, published on 13 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Calero VeraSMART versions prior to 2022 R1 use static ASP.NET/IIS machineKey values configured for the VeraSMART web application and stored in C:\\Program Files (x86)\\Veramark\\VeraSMART\\WebRoot\\web.config. An attacker who obtains these keys can craft a valid ASP.NET ViewState payload that passes integrity validation and is accepted by the application, resulting in server-side deserialization and remote code execution in the context of the IIS application.

Weakness: CWE-321 (Use of Hard-coded Cryptographic Key)

## Which versions are affected by CVE-2026-26335?

It affects 1 product.


Products: Calero Verasmart.

## How do I fix CVE-2026-26335?

No fix has been published for CVE-2026-26335 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-26335 being exploited?

There is no known exploitation of CVE-2026-26335 in the wild and no public exploit code.

Public exploit code:

- https://github.com/mbanyamer/CVE-2026-26335-Calero-VeraSMART-RCE (github_poc): https://github.com/mbanyamer/CVE-2026-26335-Calero-VeraSMART-RCE
- Repetier-Server 1.4.10 - Path Traversal (exploitdb)

## Other vulnerabilities in Calero VeraSMART

- [CVE-2026-26333](https://insights.sbomify.com/CVE-2026-26333/): Calero VeraSMART < 2022 R1 .NET Remoting Arbitrary File Read Leading to ViewState RCE (critical 10.0)
- [CVE-2026-26334](https://insights.sbomify.com/CVE-2026-26334/): Calero VeraSMART < 2026 R1 Hardcoded Static AES Keys Allow Decryption of Service Credentials (high 8.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-26335 and fix it if it is affected.

What it is: CVE-2026-26335 is a critical unsafe deserialization vulnerability in Calero VeraSMART, published on 13 Feb 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-2026-26335 in the wild and no public exploit code.

Affected product: Calero VeraSMART. 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-2026-26335/ (Markdown: https://insights.sbomify.com/CVE-2026-26335/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-26335
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-26335
- OSV: https://osv.dev/vulnerability/CVE-2026-26335

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-26335/
Summaries are generated and may contain mistakes; the official description above is the record.