# CVE-2026-16268: Newsletters < 4.16 - Unauthenticated Server-Side Request Forgery via SNS Bounce Handler

> Unauthenticated attackers can force the Newsletters WordPress plugin to fetch arbitrary URLs, enabling internal network access and potential data exposure.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Aug 2026
- **Updated:** 6 Aug 2026
- **Also known as:** GHSA-mhrm-79mh-vhfj

## What is CVE-2026-16268?

CVE-2026-16268 is a high-severity server-side request forgery vulnerability in Unknown Newsletters, published on 6 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Newsletters WordPress plugin before 4.16 does not authenticate or validate a bounce-processing request before fetching a user-supplied URL on the server side, allowing unauthenticated attackers to make the site issue requests to arbitrary internal or external hosts.

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

## Which versions are affected by CVE-2026-16268?


## How do I fix CVE-2026-16268?

No fix has been published for CVE-2026-16268 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-16268 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-16268 exists.

Public exploit code:

- Newsletters < 4.16 - Unauthenticated SSRF via SNS Bounce Handler (nuclei): http/cves/2026/CVE-2026-16268.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-16268 and fix it if it is affected.

What it is: CVE-2026-16268 is a high-severity server-side request forgery vulnerability in Unknown Newsletters, published on 6 Aug 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-2026-16268 exists.

Affected product: Unknown Newsletters. 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-2026-16268/ (Markdown: https://insights.sbomify.com/CVE-2026-16268/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-16268
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-16268
- OSV: https://osv.dev/vulnerability/CVE-2026-16268

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-16268/
Summaries are generated and may contain mistakes; the official description above is the record.