# CVE-2026-45711: axllent Mailpit path traversal in mailpit dump command

Source: https://junglewise.ai/threats/cve-2026-45711-axllent-mailpit-path-traversal-in-mailpit-dump-command  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-20. Updated: 2026-07-20  
License: CC BY 4.0 with a link back

CVE-2026-45711 · Severity: medium · CVSS 5.9 · Published 2026-07-20

Mailpit is an email testing tool used by developers to capture and view outgoing emails during software development. A security flaw in its data export command allows a malicious server to trick the tool into writing files to unauthorized locations on the user's computer. This could allow an attacker to overwrite sensitive system files, potentially leading to system instability or unauthorized access if the user connects to a compromised or untrusted Mailpit instance.

Technologies: [Axllent Mailpit](https://junglewise.ai/threats/technologies/mailpit), [github.com/axllent/mailpit (Go)](https://junglewise.ai/threats/technologies/github-com-axllent-mailpit). Vendors: [Axllent](https://junglewise.ai/threats/vendors/axllent), [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-45711 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-45711 being exploited in the wild.

**How severe is CVE-2026-45711?** Medium severity, with a CVSS score of 5.9, published 20 July 2026.

**Which products and versions are affected?** Axllent Mailpit < 1.30.0; github.com/axllent/mailpit (Go) < 1.30.0, SEMVER:introduced=0,fixed=1.30.0.

**Is there a fix for CVE-2026-45711?** Yes. github.com/axllent/mailpit (Go): upgrade to 1.30.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-45711 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-45711?** Check whether you run Axllent Mailpit or github.com/axllent/mailpit (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/axllent/mailpit (Go): upgrade to 1.30.0 or later

  ```sh
  go get github.com/axllent/mailpit@v1.30.0
  ```


## Technical details

A path traversal vulnerability exists in the 'mailpit dump --http' sub-command of Mailpit prior to version 1.30.0. The tool downloads messages from a remote instance and uses the message ID field from the server's JSON response to construct local filenames using 'path.Join'. Because 'path.Join' silently normalizes '..' segments and the tool lacks a 'filepath.Rel' containment check, a malicious server can provide IDs containing traversal sequences. This allows an attacker to write arbitrary bytes (with a .eml extension) to any path the executing user has write permissions for. Exploitation requires the user to connect the tool to a malicious or compromised Mailpit-compatible HTTP server. The issue is patched in version 1.30.0.

## Affected products

- axllent Mailpit < 1.30.0

## Identifiers

- CVE-2026-45711
- GHSA-qx5x-85p8-vg4j
- GO-2026-5599

## Timeline

- 2026-05-14: patched: Version 1.30.0 released with fix.
- 2026-07-20: disclosed: CVE-2026-45711 published.

## References

- [https://github.com/axllent/mailpit/releases/tag/v1.30.0](https://github.com/axllent/mailpit/releases/tag/v1.30.0)
- [https://github.com/axllent/mailpit/security/advisories/GHSA-qx5x-85p8-vg4j](https://github.com/axllent/mailpit/security/advisories/GHSA-qx5x-85p8-vg4j)

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