# CVE-2026-112178: MISP Proposal ACL Bypass: Incomplete Distribution Level Check in Shadow Attribute Access Control

> Attackers can view unauthorized proposal data on attributes due to flawed distribution level checks in MISP.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/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:** 19 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** GHSA-9h3q-39v8-fmg5

## What is CVE-2026-112178?

CVE-2026-112178 is a high-severity missing authorization vulnerability in MISP, published on 19 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

MISP contains an access control flaw in the proposal (shadow attribute) visibility logic. The authorization check accepted any attribute or object carrying one of the user's sharing groups without verifying the distribution level, and denied the owning organisation access to proposals on its own organisation-only attributes.

- A user belonging to a sharing group could view proposals on attributes or objects with that sharing group, regardless of the attribute's distribution level (levels 1-3 should restrict visibility)

- The owning organisation could not view proposals on its own org-only attributes

Security impact: Unauthorized disclosure of proposed attribute changes to users who should not have access based on distribution level restrictions.

Affected: <2.5.48

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-112178?


## How do I fix CVE-2026-112178?

No fix has been published for CVE-2026-112178 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-112178 being exploited?

There is no known exploitation of CVE-2026-112178 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-112178 and fix it if it is affected.

What it is: CVE-2026-112178 is a high-severity missing authorization vulnerability in MISP, published on 19 Oct 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-2026-112178 in the wild and no public exploit code.

Affected product: MISP. 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-2026-112178/ (Markdown: https://insights.sbomify.com/CVE-2026-112178/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-112178
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-112178
- OSV: https://osv.dev/vulnerability/CVE-2026-112178

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-112178/
Summaries are generated and may contain mistakes; the official description above is the record.