# CVE-2026-40168: Postiz has Server-Side Request Forgery via Redirect Bypass in /api/public/stream

> An attacker can exploit a redirect bypass in the stream endpoint to force the server to access internal resources, potentially exposing sensitive data.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Apr 2026
- **Updated:** 13 Apr 2026
- **Also known as:** GHSA-34w8-5j2v-h6ww

## What is CVE-2026-40168?

CVE-2026-40168 is a high-severity server-side request forgery vulnerability in gitroomhq postiz-app, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Postiz is an AI social media scheduling tool. Prior to 2.21.5, the /api/public/stream endpoint is vulnerable to SSRF. Although the application validates the initially supplied URL and blocks direct private/internal hosts, it does not re-validate the final destination after HTTP redirects. As a result, an attacker can supply a public HTTPS URL that passes validation and then redirects the server-side request to an internal resource.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-40168?

It affects 1 product.


Products: Gitroom Postiz.

## How do I fix CVE-2026-40168?

No fix has been published for CVE-2026-40168 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-40168 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40168 exists.

## Other vulnerabilities in gitroomhq postiz-app

- [CVE-2026-42298](https://insights.sbomify.com/CVE-2026-42298/): Postiz: Arbitrary Code Execution and Token Exfiltration in pr-docker-build.yml via untrusted Dockerfile.dev (critical 10.0)
- [CVE-2026-42556](https://insights.sbomify.com/CVE-2026-42556/): Postiz stored XSS in public preview page (high 8.9)
- [CVE-2026-40487](https://insights.sbomify.com/CVE-2026-40487/): Postiz Has Unrestricted File Upload via MIME Type Spoofing that Leads to Stored XSS (high 8.9)
- [CVE-2026-34577](https://insights.sbomify.com/CVE-2026-34577/): Postiz: Unauthenticated Full-Read SSRF via /public/stream Endpoint with Trivially Bypassable Extension Check (high 8.6)
- [CVE-2026-34576](https://insights.sbomify.com/CVE-2026-34576/): Postiz: SSRF in upload-from-url endpoint allows fetching internal resources and cloud metadata (high 8.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40168 and fix it if it is affected.

What it is: CVE-2026-40168 is a high-severity server-side request forgery vulnerability in gitroomhq postiz-app, published on 10 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40168 exists.

Affected product: gitroomhq postiz-app. 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-2026-40168/ (Markdown: https://insights.sbomify.com/CVE-2026-40168/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40168
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40168
- OSV: https://osv.dev/vulnerability/CVE-2026-40168

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40168/
Summaries are generated and may contain mistakes; the official description above is the record.