# CVE-2026-103235: MISP Event Delegation Mass Assignment Allows Retargeting Delegation to Arbitrary Events

> Authenticated attackers can exploit mass assignment in MISP delegation to read arbitrary events and transfer ownership by manipulating event IDs.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/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:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-j2mf-q9c3-gwxw

## What is CVE-2026-103235?

CVE-2026-103235 is a high-severity missing authorization vulnerability in MISP, published on 30 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

MISP contains a mass assignment vulnerability in the event delegation feature. When a user with delegation permission submits a delegation request, the application authorized the user against the event identified in the URL but then persisted the entire submitted record, including caller-supplied fields such as the primary key and event_id.

An authenticated attacker could inject a primary key or event_id into the delegation payload to retarget an existing delegation record to any event on the instance. Because a delegation row grants the requesting organisation read access to the event it references, this effectively granted read access to arbitrary events belonging to other organisations. If the target organisation subsequently accepted the delegation, ownership of the event was transferred and the original record was deleted.

Preconditions:

- An authenticated user with the delegation permission (perm_delegate)

- The MISP.delegation server setting must be enabled

Impact:

- Confidentiality: read access to any event on the instance

- Integrity: overwriting existing delegation records and transferring event ownership

Affected versions: MISP < 2.5.48

Weakness: CWE-915 (Improperly Controlled Modification of Dynamically-Determined Object Attributes), CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-103235?


## How do I fix CVE-2026-103235?

No fix has been published for CVE-2026-103235 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-103235 being exploited?

There is no known exploitation of CVE-2026-103235 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-103235 and fix it if it is affected.

What it is: CVE-2026-103235 is a high-severity missing authorization vulnerability in MISP, published on 30 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-2026-103235 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-2026-103235/ (Markdown: https://insights.sbomify.com/CVE-2026-103235/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-103235
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103235
- OSV: https://osv.dev/vulnerability/CVE-2026-103235

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-103235/
Summaries are generated and may contain mistakes; the official description above is the record.