{"id":"DEBIAN-CVE-2026-27601","details":"Underscore.js is a utility-belt library for JavaScript. Prior to 1.13.8, the _.flatten and _.isEqual functions use recursion without a depth limit. Under very specific conditions, detailed below, an attacker could exploit this in a Denial of Service (DoS) attack by triggering a stack overflow. Untrusted input must be used to create a recursive datastructure, for example using JSON.parse, with no enforced depth limit. The datastructure thus created must be passed to _.flatten or _.isEqual. In the case of _.flatten, the vulnerability can only be exploited if it is possible for a remote client to prepare a datastructure that consists of arrays at all levels AND if no finite depth limit is passed as the second argument to _.flatten. In the case of _.isEqual, the vulnerability can only be exploited if there exists a code path in which two distinct datastructures that were submitted by the same remote client are compared using _.isEqual. For example, if a client submits data that are stored in a database, and the same client can later submit another datastructure that is then compared to the data that were saved in the database previously, OR if a client submits a single request, but its data are parsed twice, creating two non-identical but equivalent datastructures that are then compared. Exceptions originating from the call to _.flatten or _.isEqual, as a result of a stack overflow, are not being caught. This vulnerability is fixed in 1.13.8.","modified":"2026-09-01T16:06:36.729130234Z","published":"2026-03-03T23:15:55.560Z","upstream":["CVE-2026-27601"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-27601"}],"affected":[{"package":{"name":"underscore","ecosystem":"Debian:12","purl":"pkg:deb/debian/underscore?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13.4~dfsg+~1.11.4-3","1.13.7~dfsg+~1.13.0-1","1.13.7~dfsg+~1.13.0-2","1.13.7~dfsg+~1.13.0-3","1.13.7~dfsg+~1.13.0-4","1.13.7~dfsg+~1.13.0-5","1.13.7~dfsg+~1.13.0-6","1.13.8~dfsg+~1.13.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27601.json"}},{"package":{"name":"underscore","ecosystem":"Debian:13","purl":"pkg:deb/debian/underscore?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13.4~dfsg+~1.11.4-3","1.13.7~dfsg+~1.13.0-1","1.13.7~dfsg+~1.13.0-2","1.13.7~dfsg+~1.13.0-3","1.13.7~dfsg+~1.13.0-4","1.13.7~dfsg+~1.13.0-5","1.13.7~dfsg+~1.13.0-6","1.13.8~dfsg+~1.13.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27601.json"}},{"package":{"name":"underscore","ecosystem":"Debian:14","purl":"pkg:deb/debian/underscore?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.13.8~dfsg+~1.13.0-1"}]}],"versions":["1.13.4~dfsg+~1.11.4-3","1.13.7~dfsg+~1.13.0-1","1.13.7~dfsg+~1.13.0-2","1.13.7~dfsg+~1.13.0-3","1.13.7~dfsg+~1.13.0-4","1.13.7~dfsg+~1.13.0-5","1.13.7~dfsg+~1.13.0-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27601.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}