{"id":1260,"date":"2026-06-10T18:14:44","date_gmt":"2026-06-10T18:14:44","guid":{"rendered":"https:\/\/thedigitalfortress.us\/?p=1260"},"modified":"2026-06-10T18:14:44","modified_gmt":"2026-06-10T18:14:44","slug":"unpatched-langflow-flaw-cve-2026-5027-exploited-for-unauthenticated-rce","status":"publish","type":"post","link":"https:\/\/thedigitalfortress.us\/?p=1260","title":{"rendered":"Unpatched Langflow Flaw CVE-2026-5027 Exploited for Unauthenticated RCE"},"content":{"rendered":"<div>\n<p><span class=\"p-author\"><i class=\"icon-font icon-user\">\ue804<\/i><span class=\"author\">Ravie Lakshmanan<\/span><i class=\"icon-font icon-calendar\">\ue802<\/i><span class=\"author\">Jun 10, 2026<\/span><\/span><span class=\"p-tags\">Vulnerability \/ Open Source<\/span><\/p>\n<\/div>\n<div id=\"articlebody\">\n<div class=\"separator\" style=\"clear: both;\"><a href=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEidDfz-Q5s2ON-nc6gW-4Lgw1yMocr3YiLP82vXcoWHcs6-_ICHWHZsciCnM2aU4kBZ2yyCJ622deCwKAXZdOFVyIoG41JC7SHyXIG6soj-RrFySsKHp2N51PpbGb7LxJWXvqOXE6GTap75h_QIjH78l0Ys__M_4EtgxMgymWgCS1vfdmWmwgpkW1TIq61I\/s1700-e365\/lang.png\" style=\"display: block;  text-align: center; clear: left; float: left;\"><\/a><\/div>\n<p>A high-severity unpatched security flaw in Langflow, an open-source low-code platform to build artificial intelligence (AI) applications, has come under active exploitation in the wild, according to <a href=\"https:\/\/www.linkedin.com\/posts\/ccondon_kevs-share-7470128376624783361-Ot2c\/\">findings<\/a> from VulnCheck.<\/p>\n<p>The vulnerability in question is <a href=\"https:\/\/nvd.nist.gov\/vuln\/detail\/cve-2026-5027\">CVE-2026-5027<\/a> (CVSS score: 8.8), a case of path traversal that could allow an attacker to write files to arbitrary locations.<\/p>\n<p>\u00abThe &#8216;POST \/api\/v2\/files&#8217; endpoint does not sanitize the &#8216;filename&#8217; parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences (&#8216;..\/&#8217;),\u00bb Tenable, which discovered the flaw, <a href=\"https:\/\/www.tenable.com\/security\/research\/tra-2026-26\">said<\/a> in an alert released in late March 2026.<\/p>\n<p>The cybersecurity company said it attempted to contact the project maintainers three times in January and February 2026, before disclosing details of the issue on March 27.<\/p>\n<p>Caitlin Condon, vice president of security research at VulnCheck, said in a LinkedIn post that the vulnerability enables remote code execution.<\/p>\n<div class=\"dog_two clear\">\n<div class=\"cf\"><a href=\"https:\/\/thehackernews.uk\/ai-cant-stop-d\" rel=\"nofollow noopener sponsored\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" class=\"lazyload\" alt=\"Cybersecurity\" src=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEjPEV6-530TOlxG6PjrmdlY623wpBwduZ7t1HV6flcmO5R4q4AmfixDUzW0CrhlvMVNWbhvOIso-UDNTka4W_W9Chrdj_dglwBZwi7DuePM2IMIl-hfUYVIqBXgfpr_2619K8Gptb4LzwJ6gUbi7lWl2M8AFQJsHEaw63Q7tZ6708YGruiHrr0Y2W9YYxLQ\/s728-e100\/ThreatLocker-d.png\" width=\"729\" height=\"91\"\/><\/a><\/div>\n<\/div>\n<p>\u00abBecause Langflow enables unauthenticated auto-login by default, no credentials are required to reach the vulnerable endpoint, and a single unauthenticated request is sufficient to obtain a valid session token before proceeding with exploitation,\u00bb Condon added.<\/p>\n<p>Exploitation efforts so far appear to weaponize the bug to write test files on victim systems. Data from Censys shows that there are about 7,000 Langflow instances publicly exposed on the internet, with a majority of them located in North America.<\/p>\n<p>The attack effort follows a flurry of exploitation activity targeting other Langflow vulnerabilities this year, including <a href=\"https:\/\/viz.greynoise.io\/tags\/langflow-untrusted-control-sphere-inclusion-cve-2026-0770-rce-attempt\">CVE-2026-0770<\/a>, CVE-2026-33017, <a href=\"https:\/\/www.crowdsec.net\/vulntracking-report\/cve-2026-21445-langflow-authentication-bypass-exploitation\">CVE-2026-21445<\/a>, and CVE-2025-34291, the last of which has been weaponized by the Iranian state-sponsored group known as MuddyWater.<\/p>\n<p>\u00abThe activity underscores a growing trend of attackers targeting the infrastructure and tooling that organizations use to build and deploy AI applications,\u00bb the company said in a statement shared with The Hacker News.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>\ue804Ravie Lakshmanan\ue802Jun 10, 2026Vulnerability \/ Open Source A high-severity unpatched security flaw in Langflow, an open-source low-code platform to build artificial intelligence (AI) applications, has come under active exploitation in&hellip;<\/p>\n","protected":false},"author":1,"featured_media":1261,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[1998,128,70,796,316,725,721],"class_list":["post-1260","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-cve20265027","tag-exploited","tag-flaw","tag-langflow","tag-rce","tag-unauthenticated","tag-unpatched"],"_links":{"self":[{"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/posts\/1260","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1260"}],"version-history":[{"count":0,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/posts\/1260\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=\/wp\/v2\/media\/1261"}],"wp:attachment":[{"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1260"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1260"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/thedigitalfortress.us\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1260"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}