CVE-2025-54799

Lego does not enforce HTTPS

LOW
2.3
CVSS Score
Published: August 7, 2025 at 12:04 AM UTC
Updated: June 17, 2026 at 09:40 AM UTC
1 product affected across 1 vendorLego

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Severity
LOW2.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

Let's Encrypt client and ACME library written in Go (Lego). In versions 4.25.1 and below, the github.com/go-acme/lego/v4/acme/api package (thus the lego library and the lego cli as well) don't enforce HTTPS when talking to CAs as an ACME client. Unlike the http-01 challenge which solves an ACME challenge over unencrypted HTTP, the ACME protocol requires HTTPS when a client communicates with the CA to performs ACME functions. However, the library fails to enforce HTTPS both in the original discover URL (configured by the library user) and in the subsequent addresses returned by the CAs in the directory and order objects. If users input HTTP URLs or CAs misconfigure endpoints, protocol operations occur over HTTP instead of HTTPS. This compromises privacy by exposing request/response details like account and request identifiers to network attackers. This was fixed in version 4.25.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.25.2
Affected range stops below 4.25.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

2.3LOWGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-319

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