{"id":"CVE-2026-77412","kind":"vulnerability","aliases":["CVE-2026-77412","GHSA-4v58-74mf-rjx3","GO-2026-6494"],"related":[],"title":"RabbitMQ amqp091-go: Denial of Service via Malicious Field Length in AMQP Client in github.com/rabbitmq/amqp091-go","description":"RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, readField in read.go reads the length of an AMQP byte-array field with type tag x into a signed int32 and passes the value directly to make when allocating the field buffer. A malicious or compromised broker can encode a value such as 0xFFFFFFFF, which becomes -1 and causes a len out of range runtime panic. The panic escapes the network reader goroutine and terminates the client process, including during connection.start server properties or message header table parsing. This issue is fixed in version 1.13.0.","summary":"The amqp091-go Go client for RabbitMQ crashes its whole process when a broker sends a byte-array field with a length of 0xFFFFFFFF, because the length is read as a signed int32 and passed to make. An attacker who controls or compromises the broker can therefore take down any application using the client.","severity":"high","cvss":8.9,"epss":0.00524,"exploited":false,"exploited_at":null,"products":[{"name":"github.com/rabbitmq/amqp091-go","fixed":["1.13.0"],"affected":"< 1.13.0","ecosystem":"go"}],"ecosystems":["go"],"tags":["amqp","go","golang","package","rabbitmq"],"not_affected_if":["fully-trusted-broker","no-go-client","version-1.13.0-or-later"],"how_to_check":"go list -m github.com/rabbitmq/amqp091-go\ngrep amqp091-go go.mod\nAny version below 1.13.0 is affected.","fix":"Upgrade github.com/rabbitmq/amqp091-go to 1.13.0 or later, then rebuild and redeploy.","status":"open","published_at":"2026-09-16T15:17:50+00:00","first_seen_at":"2026-10-23T19:13:08+00:00","triaged_at":"2026-10-23T21:43:51+00:00","updated_at":"2026-10-23T21:43:51+00:00","category":"package","confidence":0.85,"triage":{"at":"2026-10-23T21:43:51Z","model":"claude-haiku-5-5","output":{"fix":"Upgrade github.com/rabbitmq/amqp091-go to 1.13.0 or later, then rebuild and redeploy.","reach":"network","impact":"medium","summary":"The amqp091-go Go client for RabbitMQ crashes its whole process when a broker sends a byte-array field with a length of 0xFFFFFFFF, because the length is read as a signed int32 and passed to make. An attacker who controls or compromises the broker can therefore take down any application using the client.","category":"package","who_cares":["go","rabbitmq","amqp","golang"],"confidence":0.85,"needs_auth":"unknown","worst_case":"A malicious broker crashes the client process, causing denial of service.","analyst_note":"","how_to_check":"go list -m github.com/rabbitmq/amqp091-go\ngrep amqp091-go go.mod\nAny version below 1.13.0 is affected.","needs_analyst":false,"not_affected_if":["version-1.13.0-or-later","no-go-client","fully-trusted-broker"],"user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000817,"input_tokens":3037,"output_tokens":1026,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-1':157C '-2026':20A,28A,31A '-6494':29A '-77412':21A,32A '/rabbitmq/amqp091-go':18A,35A '0.9.1':105C '0xffffffff':66B,154C '1.13.0':109C,195C '4v58':24A '74mf':25A 'alloc':139C 'amqp':13A,36B,104C,118C 'amqp091':3A,43B,99C 'amqp091-go':2A,42B,98C 'applic':93B 'array':60B,121C 'attack':81B 'becom':156C 'broker':55B,87B,147C 'buffer':142C 'byte':59B,120C 'byte-array':58B,119C 'caus':159C 'client':14A,46B,96B,106C,177C 'compromis':85B,146C 'connection.start':181C 'control':83B 'crash':49B 'cve':19A,30A 'denial':5A 'direct':135C 'encod':149C 'escap':169C 'field':10A,61B,122C,141C 'fix':192C 'ghsa':23A 'ghsa-4v58-74mf-rjx3':22A 'github.com':17A,34A 'github.com/rabbitmq/amqp091-go':16A,33A 'go':4A,27A,37B,44B,45B,100C,103C 'golang':38B 'goroutin':173C 'header':186C 'includ':179C 'int32':75B,130C 'issu':190C 'len':161C 'length':11A,64B,69B,115C 'make':79B,137C 'malici':9A,144C 'messag':185C 'network':171C 'packag':39B 'panic':166C,168C 'pars':188C 'pass':77B,132C 'prior':107C 'process':52B,178C 'properti':183C 'rabbitmq':1A,40B,48B,97C 'rang':164C 'read':71B,113C 'read.go':112C 'reader':172C 'readfield':110C 'rjx3':26A 'runtim':165C 'send':56B 'server':182C 'servic':7A 'sign':74B,129C 'tabl':187C 'tag':125C 'take':90B 'termin':175C 'therefor':89B 'type':124C 'use':94B 'valu':134C,151C 'version':194C 'via':8A 'whole':51B 'x':126C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-09-16T15:17:50+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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-advisories@github.com","poc_count":0,"sources":[{"source":"govuln","external_id":"GO-2026-6494","url":"https://pkg.go.dev/vuln/GO-2026-6494","severity":null,"published_at":"2026-10-01T20:23:56+00:00","modified_at":"2026-10-01T20:23:56+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-2026-77412","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-77412","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-2026-77412","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77412","severity":null,"published_at":"2026-09-16T15:17:50+00:00","modified_at":"2026-09-23T18:19:19+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"}