{"id":"CVE-2026-95859","kind":"vulnerability","aliases":["CVE-2026-95859"],"related":[],"title":"libp2p-rust Gossipsub: unauthenticated peers can exhaust memory via GRAFT","description":"libp2p-rust is the official Rust language implementation of the libp2p networking stack. Prior to 0.49.5, Gossipsub GRAFT control-message handling unconditionally adds attacker-supplied topic hashes to connected_peer.topics without confirming that the peer previously subscribed to those topics. A remote unauthenticated peer that can reach a Gossipsub listener can repeatedly send novel GRAFT topics, causing cumulative per-peer memory growth that is not bounded by subscription filters, peer scoring, or per-message size limits. This can exhaust process memory and cause a denial of service. This issue is fixed in version 0.49.5.","summary":"libp2p-rust, the Rust implementation of the libp2p networking stack, accepts Gossipsub GRAFT messages for topics a peer never subscribed to, storing each new topic hash per peer. A remote unauthenticated peer can keep sending new topics to grow memory until the process runs out and crashes (denial of service).","severity":"high","cvss":8.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["gossipsub","libp2p","p2p-nodes","package","rust"],"not_affected_if":["no-gossipsub-listener","not-using-libp2p"],"how_to_check":"Check the libp2p-gossipsub crate version in Cargo.lock; affected if below 0.49.5.","fix":"Upgrade libp2p-gossipsub (libp2p-rust) to 0.49.5 or later.","status":"open","published_at":"2026-10-16T16:22:44+00:00","first_seen_at":"2026-10-23T21:57:13+00:00","triaged_at":"2026-10-23T22:39:06+00:00","updated_at":"2026-10-23T22:39:06+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-23T22:39:06Z","model":"claude-haiku-5-5","output":{"fix":"Upgrade libp2p-gossipsub (libp2p-rust) to 0.49.5 or later.","reach":"network","title":"libp2p-rust Gossipsub: unauthenticated peers can exhaust memory via GRAFT","impact":"medium","summary":"libp2p-rust, the Rust implementation of the libp2p networking stack, accepts Gossipsub GRAFT messages for topics a peer never subscribed to, storing each new topic hash per peer. A remote unauthenticated peer can keep sending new topics to grow memory until the process runs out and crashes (denial of service).","category":"package","who_cares":["rust","libp2p","gossipsub","p2p-nodes"],"confidence":0.7,"needs_auth":"no","worst_case":"Remote peer exhausts process memory, crashing the node.","analyst_note":"","how_to_check":"Check the libp2p-gossipsub crate version in Cargo.lock; affected if below 0.49.5.\nunknown","needs_analyst":false,"not_affected_if":["no-gossipsub-listener","not-using-libp2p"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"high"},"cost_usd":0.00051,"input_tokens":3018,"output_tokens":417,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-95859':14A,17A '0.49.5':92C,173C 'accept':36B 'add':100C 'attack':102C 'attacker-suppli':101C 'bound':144C 'caus':134C,162C 'confirm':109C 'connected_peer.topics':107C 'control':96C 'control-messag':95C 'crash':72B 'cumul':135C 'cve':12A,15A 'denial':73B,164C 'exhaust':8A,158C 'filter':147C 'fix':170C 'gossipsub':4A,18B,37B,93C,126C 'graft':11A,38B,94C,132C 'grow':64B 'growth':140C 'handl':98C 'hash':51B,105C 'implement':30B,84C 'issu':168C 'keep':59B 'languag':83C 'libp2p':2A,19B,26B,33B,77C,87C 'libp2p-rust':1A,25B,76C 'limit':155C 'listen':127C 'memori':9A,65B,139C,160C 'messag':39B,97C,153C 'network':34B,88C 'never':44B 'new':49B,61B 'node':22B 'novel':131C 'offici':81C 'p2p':21B 'p2p-nodes':20B 'packag':23B 'peer':6A,43B,53B,57B,112C,121C,138C,148C 'per':52B,137C,152C 'per-messag':151C 'per-peer':136C 'previous':113C 'prior':90C 'process':68B,159C 'reach':124C 'remot':55B,119C 'repeat':129C 'run':69B 'rust':3A,24B,27B,29B,78C,82C 'score':149C 'send':60B,130C 'servic':75B,166C 'size':154C 'stack':35B,89C 'store':47B 'subscrib':45B,114C 'subscript':146C 'suppli':103C 'topic':41B,50B,62B,104C,117C,133C 'unauthent':5A,56B,120C 'uncondit':99C 'version':172C 'via':10A 'without':108C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-16T16:22:44+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/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":"nvd","external_id":"CVE-2026-95859","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-95859","severity":null,"published_at":"2026-10-16T16:22:44+00:00","modified_at":"2026-10-21T03:17:20+00:00","first_seen_at":"2026-10-23T21:57:13+00:00","fetched_at":"2026-10-23T22:28:55+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"}