# CVE-2026-125755: Nodemailer 3.0.0 before 10.4.1 Recipient Allow-List Bypass via addressparser


- **Severity:** High 8.3 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 10 Nov 2026
- **Updated:** 10 Nov 2026
- **Also known as:** CLSA-2026-1794329057, CLSA-2026-1794334703, CLSA-2026-1794464097, GHSA-3q53-mvfw-q9v8, GHSA-j5rx-43mx-fv6c, UBUNTU-CVE-2026-125755

## What is CVE-2026-125755?

CVE-2026-125755 is a high-severity vulnerability in nodemailer, published on 10 Nov 2026. 

### Official description

Nodemailer 3.0.0 before 10.4.1 contains an address parsing flaw in addressparser that truncates domains at folding whitespace or comments before a dot, allowing attackers to bypass recipient domain restrictions. Attackers can submit crafted to, cc, bcc or replyTo addresses that pass RFC 5322 domain checks but deliver mail to an attacker-chosen address under the application's sender identity.

Weakness: CWE-436 (Interpretation Conflict)

## Which versions are affected by CVE-2026-125755?


## How do I fix CVE-2026-125755?

Upgrade to a fixed version.

## Is CVE-2026-125755 being exploited?

There is no known exploitation of CVE-2026-125755 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-125755 and fix it if it is affected.

What it is: CVE-2026-125755 is a high-severity vulnerability in nodemailer, published on 10 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-125755 in the wild and no public exploit code.

Affected product: nodemailer. 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-2026-125755/ (Markdown: https://insights.sbomify.com/CVE-2026-125755/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-125755
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-125755
- OSV: https://osv.dev/vulnerability/CVE-2026-125755

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-125755/
Summaries are generated and may contain mistakes; the official description above is the record.