# CVE-2026-35391: Security feature bypass in webmail

> Attackers can spoof IP addresses via X-Forwarded-For to bypass rate limits and forge audit logs in Bulwark Webmail.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/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:** Not needed
- **Fix available:** No
- **Published:** 6 Apr 2026
- **Updated:** 7 Apr 2026
- **Also known as:** GHSA-7pj2-232x-6698

## What is CVE-2026-35391?

CVE-2026-35391 is a high-severity vulnerability in bulwarkmail webmail, published on 6 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.4.11, the getClientIP() function in lib/admin/session.ts trusted the first (leftmost) entry of the X-Forwarded-For header, which is fully controlled by the client. An attacker could forge their source IP address to bypass IP-based rate limiting (enabling brute-force attacks against the admin login) or forge audit log entries (making malicious activity appear to originate from arbitrary IP addresses). This vulnerability is fixed in 1.4.11.

Weakness: CWE-348 (Use of Less Trusted Source)

## Which versions are affected by CVE-2026-35391?

It affects 1 product.


Products: Bulwarkmail Webmail.

## How do I fix CVE-2026-35391?

No fix has been published for CVE-2026-35391 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-35391 being exploited?

There is no known exploitation of CVE-2026-35391 in the wild and no public exploit code.

## Other vulnerabilities in bulwarkmail webmail

- [CVE-2026-35389](https://insights.sbomify.com/CVE-2026-35389/): Bulwark Webmail S/MIME signature verification accepted self-signed certificates (high 8.7)
- [CVE-2026-34833](https://insights.sbomify.com/CVE-2026-34833/): Bulwark Webmail: Information Exposure: password returned in /api/auth/session (high 8.7)
- [CVE-2026-34834](https://insights.sbomify.com/CVE-2026-34834/): Bulwark Webmail: Authentication Bypass in verifyIdentity() due to missing cookie validation (high 8.7)
- [CVE-2026-35390](https://insights.sbomify.com/CVE-2026-35390/): Content-Security-Policy was set to Report-Only mode, failing to block XSS attacks (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-35391 and fix it if it is affected.

What it is: CVE-2026-35391 is a high-severity vulnerability in bulwarkmail webmail, published on 6 Apr 2026. 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-2026-35391 in the wild and no public exploit code.

Affected product: bulwarkmail webmail. 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-2026-35391/ (Markdown: https://insights.sbomify.com/CVE-2026-35391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-35391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35391
- OSV: https://osv.dev/vulnerability/CVE-2026-35391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-35391/
Summaries are generated and may contain mistakes; the official description above is the record.