# CVE-2018-25236: Hirschmann HiOS HiSecOS Authentication Bypass via HTTP Management

> Unauthenticated remote attackers can bypass authentication in Hirschmann HiOS/HiSecOS HTTP management to gain administrative access.

- **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:** 3 Apr 2026
- **Updated:** 15 Jul 2026
- **Also known as:** GHSA-9hhf-w3pr-8g2c

## What is CVE-2018-25236?

CVE-2018-25236 is a critical authentication bypass vulnerability in Belden Hirschmann HiOS, published on 3 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Hirschmann HiOS and HiSecOS products RSP, RSPE, RSPS, RSPL, MSP, EES, EESX, GRS, OS, RED, EAGLE contain an authentication bypass vulnerability in the HTTP(S) management module that allows unauthenticated remote attackers to gain administrative access by crafting specially formed HTTP requests. Attackers can exploit improper authentication handling to obtain the authentication status and privileges of a previously authenticated user without providing valid credentials.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2018-25236?


## How do I fix CVE-2018-25236?

No fix has been published for CVE-2018-25236 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-25236 being exploited?

There is no known exploitation of CVE-2018-25236 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-25236 and fix it if it is affected.

What it is: CVE-2018-25236 is a critical authentication bypass vulnerability in Belden Hirschmann HiOS, published on 3 Apr 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-2018-25236 in the wild and no public exploit code.

Affected product: Belden Hirschmann HiOS. 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-2018-25236/ (Markdown: https://insights.sbomify.com/CVE-2018-25236/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-25236
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-25236
- OSV: https://osv.dev/vulnerability/CVE-2018-25236

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-25236/
Summaries are generated and may contain mistakes; the official description above is the record.