{"id":"CVE-2026-84298","kind":"vulnerability","aliases":["CVE-2026-84298","GHSA-9q4h-f4x5-ffq8","GO-2026-6561"],"related":[],"title":"Hatchet: Cross-tenant durable callback payload disclosure in Hatchet V1 Dispatcher in github.com/hatchet-dev/hatchet","description":"Hatchet is a platform for orchestrating background tasks, AI agents, and durable workflows at scale. Prior to 0.95.3, the V1 DurableTask stream handler stores worker-supplied task_external_id values in the durableInvocations routing map before tenant ownership is verified, and callback delivery resolves that map by task UUID without tenant identity. An authenticated tenant worker that knows another tenant's durable task UUID and keeps a stream open on the same dispatcher process can receive that task's durable callback result payload. UUIDv4 values are not enumerable, and single-tenant deployments are unaffected in practice. This issue is fixed in version 0.95.3.","summary":"Hatchet's V1 Dispatcher routes durable task callbacks by task UUID without checking tenant identity, so a worker from one tenant can receive another tenant's durable callback result payload. The attacker needs a valid worker in their own tenant and must know the victim's task UUID, which is hard to guess.","severity":"low","cvss":3.1,"epss":0.00243,"exploited":false,"exploited_at":null,"products":[{"name":"github.com/hatchet-dev/hatchet","fixed":["0.95.3"],"affected":"< 0.95.3","ecosystem":"go"}],"ecosystems":["go"],"tags":["go","hatchet","multi-tenant","package","self-hosted"],"not_affected_if":["single-tenant-deployment","version-0.95.3-or-later"],"how_to_check":"Run go list -m github.com/hatchet-dev/hatchet in each service that uses Hatchet, or check the version in go.mod; versions below 0.95.3 are affected.","fix":"Upgrade github.com/hatchet-dev/hatchet to 0.95.3 or later.","status":"open","published_at":"2026-09-21T16:17:24+00:00","first_seen_at":"2026-10-23T19:13:08+00:00","triaged_at":"2026-10-23T21:49:23+00:00","updated_at":"2026-10-23T21:49:23+00:00","category":"package","confidence":0.8,"triage":{"at":"2026-10-23T21:49:23Z","model":"claude-haiku-5-5","output":{"fix":"Upgrade github.com/hatchet-dev/hatchet to 0.95.3 or later.","reach":"network","impact":"medium","summary":"Hatchet's V1 Dispatcher routes durable task callbacks by task UUID without checking tenant identity, so a worker from one tenant can receive another tenant's durable callback result payload. The attacker needs a valid worker in their own tenant and must know the victim's task UUID, which is hard to guess.","category":"package","who_cares":["hatchet","go","multi-tenant","self-hosted"],"confidence":0.8,"needs_auth":"yes","worst_case":"Another tenant's durable task callback result payloads are readable by an authenticated worker.","analyst_note":"","how_to_check":"Run go list -m github.com/hatchet-dev/hatchet in each service that uses Hatchet, or check the version in go.mod; versions below 0.95.3 are affected.","needs_analyst":false,"not_affected_if":["single-tenant-deployment","version-0.95.3-or-later"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"low"},"cost_usd":0.000807,"input_tokens":3063,"output_tokens":1001,"severity_before":"low"},"analyst_status":null,"analyst_note":null,"search":"'-2026':18A,26A,29A '-6561':27A '-84298':19A,30A '/hatchet-dev/hatchet':16A,33A '0.95.3':113C,200C '9q4h':22A 'agent':105C 'ai':104C 'anoth':66B,155C 'attack':74B 'authent':150C 'background':102C 'callback':6A,50B,70B,138C,177C 'check':55B 'cross':3A 'cross-ten':2A 'cve':17A,28A 'deliveri':139C 'deploy':189C 'disclosur':8A 'dispatch':12A,46B,169C 'durabl':5A,48B,69B,107C,158C,176C 'durableinvoc':129C 'durabletask':116C 'enumer':184C 'extern':124C 'f4x5':23A 'ffq8':24A 'fix':197C 'ghsa':21A 'ghsa-9q4h-f4x5-ffq8':20A 'github.com':15A,32A 'github.com/hatchet-dev/hatchet':14A,31A 'go':25A,34B 'guess':95B 'handler':118C 'hard':93B 'hatchet':1A,10A,35B,43B,96C 'host':42B 'id':125C 'ident':57B,148C 'issu':195C 'keep':162C 'know':85B,154C 'map':131C,142C 'multi':37B 'multi-ten':36B 'must':84B 'need':75B 'one':62B 'open':165C 'orchestr':101C 'ownership':134C 'packag':39B 'payload':7A,72B,179C 'platform':99C 'practic':193C 'prior':111C 'process':170C 'receiv':65B,172C 'resolv':140C 'result':71B,178C 'rout':47B,130C 'scale':110C 'self':41B 'self-host':40B 'singl':187C 'single-ten':186C 'store':119C 'stream':117C,164C 'suppli':122C 'task':49B,52B,89B,103C,123C,144C,159C,174C 'tenant':4A,38B,56B,63B,67B,82B,133C,147C,151C,156C,188C 'unaffect':191C 'uuid':53B,90B,145C,160C 'uuidv4':180C 'v1':11A,45B,115C 'valid':77B 'valu':126C,181C 'verifi':136C 'version':199C 'victim':87B 'without':54B,146C 'worker':60B,78B,121C,152C 'worker-suppli':120C 'workflow':108C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-09-21T16:17:24+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N","cvss_by":"security-advisories@github.com","poc_count":0,"sources":[{"source":"govuln","external_id":"GO-2026-6561","url":"https://pkg.go.dev/vuln/GO-2026-6561","severity":null,"published_at":"2026-10-01T20:23:38+00:00","modified_at":"2026-10-01T20:23:38+00:00","first_seen_at":"2026-10-23T19:13:08+00:00","fetched_at":"2026-10-23T19:13:08+00:00","note":null},{"source":"epss","external_id":"CVE-2026-84298","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-84298","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:43+00:00","fetched_at":"2026-10-23T19:13:43+00:00","note":null},{"source":"nvd","external_id":"CVE-2026-84298","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-84298","severity":null,"published_at":"2026-09-21T16:17:24+00:00","modified_at":"2026-09-23T18:26:49+00:00","first_seen_at":"2026-10-23T19:35:23+00:00","fetched_at":"2026-10-23T19:35:23+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}