# CVE-2026-77426: Unleash: Missing await on permission check + cross-project IDOR in admin API

> Authenticated users can bypass permission checks and access or modify cross-project feature configurations due to missing authorization validations in the admin API.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/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:** Yes
- **Published:** 22 Sep 2026
- **Updated:** 23 Sep 2026
- **Also known as:** GHSA-72h8-wp98-7hch, MINI-v6wm-97c5-phrh

## What is CVE-2026-77426?

CVE-2026-77426 is a high-severity missing authorization vulnerability in unleash, published on 22 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Unleash is an open-source feature management platform. Prior to 8.0.3, the Unleash admin API contains five authorization vulnerabilities. POST /api/admin/segments/strategies assigns the Promise returned by hasPermission without awaiting it, allowing authenticated users to modify segment assignments without UPDATE_FEATURE_STRATEGY permission for the target project and environment. GET /api/admin/projects/:projectId/features/:featureName/environments/:environment/variants does not bind the requested feature to projectId, allowing cross-project variant configuration disclosure. GET .../strategies/:strategyId uses strategyId without validating the project and feature context, allowing cross-project strategy configuration disclosure. getEnvironmentInfo does not validate that the requested feature belongs to the supplied project, allowing cross-project environment information disclosure. PUT /:projectId/tags accepts feature identifiers without verifying that they belong to the URL project, allowing cross-project tag modification. This issue is fixed in version 8.0.3.

Weakness: CWE-862 (Missing Authorization), CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-77426?

2 open source packages ship an affected version, including unleash-server.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `unleash-server` | npm | All versions | 8.0.3 |
| `unleash-server` | npm | All versions | 8.0.3 |

## How do I fix CVE-2026-77426?

Upgrade unleash-server to 8.0.3 or later.

## Is CVE-2026-77426 being exploited?

There is no known exploitation of CVE-2026-77426 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-77426 and fix it if it is affected.

What it is: CVE-2026-77426 is a high-severity missing authorization vulnerability in unleash, published on 22 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-2026-77426 in the wild and no public exploit code.

Affected packages and fixed versions:
- unleash-server (npm): affected all versions; fixed in 8.0.3
- unleash-server (npm): affected all versions; fixed in 8.0.3

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-2026-77426/ (Markdown: https://insights.sbomify.com/CVE-2026-77426/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-77426
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-77426
- OSV: https://osv.dev/vulnerability/CVE-2026-77426

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-77426/
Summaries are generated and may contain mistakes; the official description above is the record.