{"id":"DEBIAN-CVE-2026-40611","details":"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.","modified":"2026-09-01T16:06:41.625103142Z","published":"2026-04-21T18:16:52.457Z","upstream":["CVE-2026-40611"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-40611"}],"affected":[{"package":{"name":"golang-github-xenolf-lego","ecosystem":"Debian:12","purl":"pkg:deb/debian/golang-github-xenolf-lego?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.35.2-1","4.35.2-2","4.35.2-2~bpo13+1","4.35.2-3","4.35.2-3~bpo13+1","4.9.1-1","4.9.1-2","4.9.1-3","4.9.1-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40611.json"}},{"package":{"name":"golang-github-xenolf-lego","ecosystem":"Debian:13","purl":"pkg:deb/debian/golang-github-xenolf-lego?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.35.2-1","4.35.2-2","4.35.2-2~bpo13+1","4.35.2-3","4.35.2-3~bpo13+1","4.9.1-2","4.9.1-3","4.9.1-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40611.json"}},{"package":{"name":"golang-github-xenolf-lego","ecosystem":"Debian:14","purl":"pkg:deb/debian/golang-github-xenolf-lego?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.35.2-1"}]}],"versions":["4.9.1-2","4.9.1-3","4.9.1-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-40611.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}