# CVE-2025-0521: Post SMTP <= 3.0.2 - Unauthenticated Stored Cross-Site Scripting

> Unauthenticated attackers can inject arbitrary web scripts via email parameters, leading to script execution when users view affected pages.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/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:** 18 Feb 2025
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-3f9v-jhc5-p8jp

## What is CVE-2025-0521?

CVE-2025-0521 is a high-severity cross-site scripting vulnerability in saadiqbal Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App, published on 18 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Post SMTP plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the from and subject parameter in all versions up to, and including, 3.0.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2025-0521?

It affects 1 product.


Products: Wpexperts Post Smtp.

## How do I fix CVE-2025-0521?

No fix has been published for CVE-2025-0521 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-0521 being exploited?

There is no known exploitation of CVE-2025-0521 in the wild and no public exploit code.

## Other vulnerabilities in saadiqbal Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App

- [CVE-2023-6875](https://insights.sbomify.com/CVE-2023-6875/): Auth bypass in Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App (critical 9.8)
- [CVE-2023-3179](https://insights.sbomify.com/CVE-2023-3179/): POST SMTP Mailer < 2.5.7 - Account Takeover via CSRF (high 8.8)
- [CVE-2023-52233](https://insights.sbomify.com/CVE-2023-52233/): WordPress POST SMTP Mailer plugin <= 2.8.6 - Broken Access Control on API vulnerability (high 8.6)
- [CVE-2024-52436](https://insights.sbomify.com/CVE-2024-52436/): WordPress Post SMTP plugin <= 2.9.9 - SQL Injection vulnerability (high 7.6)
- [CVE-2024-5207](https://insights.sbomify.com/CVE-2024-5207/): SQL injection in Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App (high 7.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-0521 and fix it if it is affected.

What it is: CVE-2025-0521 is a high-severity cross-site scripting vulnerability in saadiqbal Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App, published on 18 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-0521 in the wild and no public exploit code.

Affected product: saadiqbal Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile 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-2025-0521/ (Markdown: https://insights.sbomify.com/CVE-2025-0521/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-0521
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-0521
- OSV: https://osv.dev/vulnerability/CVE-2025-0521

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From sbomify Insights: https://insights.sbomify.com/CVE-2025-0521/
Summaries are generated and may contain mistakes; the official description above is the record.