# CVE-2026-90447: Authentication Bypass by Spoofing in Malcolm

> An authenticated attacker can spoof a request header to bypass role-based authorization and access elevated privileges in Malcolm.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Sep 2026
- **Updated:** 2 Oct 2026
- **Also known as:** GHSA-rh2r-7hqc-wgwc

## What is CVE-2026-90447?

CVE-2026-90447 is a high-severity authentication bypass vulnerability in CISA Malcolm, published on 11 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A routing rule selects between two different authentication mechanisms for the same downstream service based on the value of a client-supplied request header, rather than on any property the client cannot control. An authenticated user in possession of a shared service credential can set this header to route around the primary role-based authorization check and reach the alternate path's fixed, elevated role instead. This allows a low-privileged authenticated attacker who knows the shared credential to perform actions reserved for a higher-privileged role.

Weakness: CWE-290 (Authentication Bypass by Spoofing)

## Which versions are affected by CVE-2026-90447?


## How do I fix CVE-2026-90447?

No fix has been published for CVE-2026-90447 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-90447 being exploited?

There is no known exploitation of CVE-2026-90447 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90447 and fix it if it is affected.

What it is: CVE-2026-90447 is a high-severity authentication bypass vulnerability in CISA Malcolm, published on 11 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-90447 in the wild and no public exploit code.

Affected product: CISA Malcolm. 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-2026-90447/ (Markdown: https://insights.sbomify.com/CVE-2026-90447/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90447
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90447
- OSV: https://osv.dev/vulnerability/CVE-2026-90447

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90447/
Summaries are generated and may contain mistakes; the official description above is the record.