# CVE-2025-52557: Mail-0 Zero Session Hijacking Via Email

> Attackers can hijack user sessions in Mail-0 Zero by sending crafted emails containing malicious JavaScript due to improper sanitization.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 Jun 2025
- **Updated:** 23 Jun 2025
- **Also known as:** GHSA-34gh-g567-hq85

## What is CVE-2025-52557?

CVE-2025-52557 is a high-severity cross-site scripting vulnerability in Mail-0 Zero, published on 21 Jun 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Mail-0's Zero is an open-source email solution. In version 0.8 it's possible for an attacker to craft an email that executes javascript leading to session hijacking due to improper sanitization. This issue has been patched in version 0.81.

Weakness: CWE-1384 (Improper Handling of Physical or Environmental Conditions)

## Which versions are affected by CVE-2025-52557?


## How do I fix CVE-2025-52557?

No fix has been published for CVE-2025-52557 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-52557 being exploited?

There is no known exploitation of CVE-2025-52557 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-52557 and fix it if it is affected.

What it is: CVE-2025-52557 is a high-severity cross-site scripting vulnerability in Mail-0 Zero, published on 21 Jun 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2025-52557 in the wild and no public exploit code.

Affected product: Mail-0 Zero. 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-2025-52557/ (Markdown: https://insights.sbomify.com/CVE-2025-52557/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-52557
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-52557
- OSV: https://osv.dev/vulnerability/CVE-2025-52557

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-52557/
Summaries are generated and may contain mistakes; the official description above is the record.