Cleartext transmission of sensitive information in lego - CVE-2025-54799
Published: April 16, 2026
Vulnerability identifier: #VU126356
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-54799
CWE-ID: CWE-319
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper transport security enforcement in github.com/go-acme/lego/v4/acme/api when communicating with ACME certificate authority endpoints. A remote attacker can intercept unencrypted ACME requests and responses to disclose sensitive information.
The issue can be triggered if the library user supplies an HTTP discovery URL or if a certificate authority returns HTTP endpoint URLs in directory or order objects.
Affected software
lego
How to mitigate CVE-2025-54799
Install security update from vendor's website.
lego - update to 4.25.2