{"id":"CVE-2026-123835","kind":"vulnerability","aliases":["CVE-2026-123835"],"related":[],"title":"JetBrains Datalore: init script upload race lets one user run code in another's computation","description":"In JetBrains Datalore before 2026.4 code execution was possible in another user's computation via an init script upload race condition","summary":"Before version 2026.4 of JetBrains Datalore, a race condition in init script upload let code run inside another user's computation. An attacker who wins the race can execute code in a session that belongs to someone else.","severity":"medium","cvss":5.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["datalore","jetbrains","other","self-hosted"],"not_affected_if":["single-user","version-2026.4-or-later"],"how_to_check":"- Check the installed Datalore version against the fixed release, `2026.4`\n- Look for a self-hosted Datalore deployment in your environment; unknown whether hosted Datalore is affected","fix":"- Datalore: move to `2026.4` or later","status":"open","published_at":"2026-11-06T17:17:21+00:00","first_seen_at":"2026-11-06T17:43:12+00:00","triaged_at":"2026-11-06T17:45:20+00:00","updated_at":"2026-11-06T17:45:20+00:00","category":"other","confidence":0.5,"triage":{"at":"2026-11-06T17:45:20Z","model":"claude-haiku-5-5","output":{"fix":"- Datalore: move to `2026.4` or later","reach":"network","title":"JetBrains Datalore: init script upload race lets one user run code in another's computation","impact":"high","summary":"Before version 2026.4 of JetBrains Datalore, a race condition in init script upload let code run inside another user's computation. An attacker who wins the race can execute code in a session that belongs to someone else.","audience":"businesses","category":"other","nicknames":[],"who_cares":["datalore","jetbrains","self-hosted"],"confidence":0.5,"fix_status":"available","needs_auth":"yes","worst_case":"code runs in another user's computation session","analyst_note":"Confirm affected deployment modes and whether hosted Datalore is affected; check the JetBrains advisory for CVE-2026-123835.","how_to_check":"- Check the installed Datalore version against the fixed release, `2026.4`\n- Look for a self-hosted Datalore deployment in your environment; unknown whether hosted Datalore is affected","plain_action":"","needs_analyst":true,"not_affected_if":["single-user","version-2026.4-or-later"],"who_is_affected":"Teams running JetBrains Datalore with multiple users who upload init scripts. The flaw is a race during upload, so a single-user installation is unlikely to be exposed. Sources do not say which deployment modes are affected.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.00067,"input_tokens":4160,"output_tokens":508,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-123835':18A,21A '-2026':17A,20A '2026.4':30B,70C 'anoth':13A,45B,76C 'attack':50B 'belong':62B 'code':11A,42B,57B,71C 'comput':15A,48B,79C 'condit':36B,86C 'cve':16A,19A 'datalor':2A,22B,33B,68C 'els':65B 'execut':56B,72C 'host':27B 'init':3A,38B,82C 'insid':44B 'jetbrain':1A,23B,32B,67C 'let':7A,41B 'one':8A 'possibl':74C 'race':6A,35B,54B,85C 'run':10A,43B 'script':4A,39B,83C 'self':26B 'self-host':25B 'session':60B 'someon':64B 'upload':5A,40B,84C 'user':9A,46B,77C 'version':29B 'via':80C 'win':52B","nicknames":[],"mitigations":[],"who_affected":"Teams running JetBrains Datalore with multiple users who upload init scripts. The flaw is a race during upload, so a single-user installation is unlikely to be exposed. Sources do not say which deployment modes are affected.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["datalore","jetbrains","medium","other","selfhosted"],"campaign_type":null,"search_a":"'-123835':18A,21A '-2026':17A,20A 'anoth':13A 'code':11A 'comput':15A 'cve':16A,19A 'datalor':2A 'init':3A 'jetbrain':1A 'let':7A 'one':8A 'race':6A 'run':10A 'script':4A 'upload':5A 'user':9A","search_b":"'2026.4':30B 'anoth':45B 'attack':50B 'belong':62B 'code':42B,57B 'comput':48B 'condit':36B 'datalor':22B,33B 'els':65B 'execut':56B 'host':27B 'init':38B 'insid':44B 'jetbrain':23B,32B 'let':41B 'race':35B,54B 'run':43B 'script':39B 'self':26B 'self-host':25B 'session':60B 'someon':64B 'upload':40B 'user':46B 'version':29B 'win':52B","search_c":"'2026.4':70C 'anoth':76C 'code':71C 'comput':79C 'condit':86C 'datalor':68C 'execut':72C 'init':82C 'jetbrain':67C 'possibl':74C 'race':85C 'script':83C 'upload':84C 'user':77C 'via':80C","first_public_at":"2026-11-06T17:17:21+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N","cvss_by":"cve@jetbrains.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-123835","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-123835","severity":null,"published_at":"2026-11-06T17:17:21+00:00","modified_at":"2026-11-06T17:17:21+00:00","first_seen_at":"2026-11-06T17:43:12+00:00","fetched_at":"2026-11-06T17:43:12+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"}