Description

Let's Encrypt client and ACME library written in Go (Lego). Prior to 4.34.0, the webroot HTTP-01 challenge provider in lego is vulnerable to arbitrary file write and deletion via path traversal. A malicious ACME server can supply a crafted challenge token containing ../ sequences, causing lego to write attacker-influenced content to any path writable by the lego process. This vulnerability is fixed in 4.34.0.

INFO

Published Date :

2026-04-21T17:58:35.221Z

Last Modified :

2026-04-21T19:17:54.210Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-40611 vulnerability.

Vendors Products
Go-acme
  • Lego
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-40611.

URL Resource
https://github.com/go-acme/lego/security/advisories/GHSA-qqx8-2xmm-jrv8 cve-icon cve-icon cve-icon
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