{"id":"CVE-2026-73101","kind":"vulnerability","aliases":["CVE-2026-73101"],"related":[],"title":"Apache Juneau: REST error responses leak internal exception details to clients","description":"Generation of Error Message Containing Sensitive Information vulnerability in Apache Juneau.\n\nThe REST server sends the internal exception class and message to clients in a \"Thrown\" response header on every error response, and can include internal exception messages in the error body, even when stack-trace rendering is disabled. This reveals implementation details to remote clients.\n\nThis issue affects Apache Juneau: through 9.2.0.\n\nUsers are recommended to upgrade to version 9.2.1, which fixes the issue.","summary":"Apache Juneau's REST server sends the internal exception class and message in a \"Thrown\" response header and sometimes in the error body, even when stack traces are disabled. An attacker who sends requests that trigger errors learns implementation details about the server.","severity":"critical","cvss":10.0,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["apache-juneau","java","package","rest"],"not_affected_if":["not-using-juneau-rest-server"],"how_to_check":"- Check the Apache Juneau version in the project's build file (for example `pom.xml` or `build.gradle`) against the affected range.\n- Send a request that triggers an error and look for a \"Thrown\" response header.","fix":"- Apache Juneau: upgrade to `9.2.1`.","status":"open","published_at":"2026-11-05T12:17:51+00:00","first_seen_at":"2026-11-05T12:38:47+00:00","triaged_at":"2026-11-05T12:40:01+00:00","updated_at":"2026-11-05T12:40:01+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-11-05T12:40:01Z","model":"claude-haiku-5-5","output":{"fix":"- Apache Juneau: upgrade to `9.2.1`.","reach":"internet","title":"Apache Juneau: REST error responses leak internal exception details to clients","impact":"low","summary":"Apache Juneau's REST server sends the internal exception class and message in a \"Thrown\" response header and sometimes in the error body, even when stack traces are disabled. An attacker who sends requests that trigger errors learns implementation details about the server.","audience":"developers","category":"package","nicknames":[],"who_cares":["java","apache-juneau","rest"],"confidence":0.7,"fix_status":"available","needs_auth":"no","worst_case":"internal exception classes and messages leak to remote clients","analyst_note":"","how_to_check":"- Check the Apache Juneau version in the project's build file (for example `pom.xml` or `build.gradle`) against the affected range.\n- Send a request that triggers an error and look for a \"Thrown\" response header.","plain_action":"","needs_analyst":false,"not_affected_if":["not-using-juneau-rest-server"],"who_is_affected":"Teams running a Java REST service built on Apache Juneau through version 9.2.0 are exposed, since every error response carries the header. Services that do not use Juneau's REST server can skip it.","user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"critical"},"cost_usd":0.000665,"input_tokens":4278,"output_tokens":474,"severity_before":"critical"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-73101':14A,17A '9.2.0':130C '9.2.1':138C 'affect':126C 'apach':1A,19B,24B,76C,127C 'apache-juneau':18B 'attack':54B 'bodi':46B,108C 'class':33B,85C 'client':11A,89C,123C 'contain':71C 'cve':12A,15A 'detail':9A,63B,120C 'disabl':52B,116C 'error':4A,45B,60B,69C,97C,107C 'even':47B,109C 'everi':96C 'except':8A,32B,84C,103C 'fix':140C 'generat':67C 'header':40B,94C 'implement':62B,119C 'includ':101C 'inform':73C 'intern':7A,31B,83C,102C 'issu':125C,142C 'java':21B 'juneau':2A,20B,25B,77C,128C 'leak':6A 'learn':61B 'messag':35B,70C,87C,104C 'packag':22B 'recommend':133C 'remot':122C 'render':114C 'request':57B 'respons':5A,39B,93C,98C 'rest':3A,23B,27B,79C 'reveal':118C 'send':29B,56B,81C 'sensit':72C 'server':28B,66B,80C 'sometim':42B 'stack':49B,112C 'stack-trac':111C 'thrown':38B,92C 'trace':50B,113C 'trigger':59B 'upgrad':135C 'user':131C 'version':137C 'vulner':74C","nicknames":[],"mitigations":[],"who_affected":"Teams running a Java REST service built on Apache Juneau through version 9.2.0 are exposed, since every error response carries the header. Services that do not use Juneau's REST server can skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"developers","plain_action":null,"pkeys":[],"ptokens":[],"labels":["apachejuneau","critical","java","package","rest"],"campaign_type":null,"first_public_at":"2026-11-05T12:17:51+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"security@apache.org","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-73101","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-73101","severity":null,"published_at":"2026-11-05T12:17:51+00:00","modified_at":"2026-11-05T12:17:51+00:00","first_seen_at":"2026-11-05T12:38:47+00:00","fetched_at":"2026-11-05T12:38:47+00:00","note":null}],"documents":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}