CVE-2025-54799

Name	CVE-2025-54799
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.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	1110531

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
golang-github-xenolf-lego (PTS)	bullseye	3.2.0-3.1	vulnerable
	bookworm	4.9.1-1	vulnerable
	forky, sid, trixie	4.9.1-2	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
golang-github-xenolf-lego	source	(unstable)	(unfixed)			1110531

Notes

[trixie] - golang-github-xenolf-lego <no-dsa> (Minor issue)
[bookworm] - golang-github-xenolf-lego <no-dsa> (Minor issue)
[bullseye] - golang-github-xenolf-lego <ignored> (minor; need both client and server misconfigured unlikely)
https://github.com/go-acme/lego/security/advisories/GHSA-q82r-2j7m-9rv4
Fixed by: https://github.com/go-acme/lego/commit/238454b5f74f3cfcbb244ff0d0dc914a4ad44b96 (v4.25.2)
Workaround: CA endpoint should enforce HTTPS instead of HTTP.