{"id":"CVE-2026-121293","kind":"vulnerability","aliases":["CVE-2026-121293"],"related":[],"title":"Arista EOS: crafted BGP message crashes routing process and resets sessions","description":"On affected EOS-based platforms, an attacker who controls a Border Gateway Protocol (BGP) peer can send a crafted BGP message over an established session with the Dynamic Path Selection (DPS) address family negotiated. This can cause the BGP process to terminate unexpectedly, resetting all BGP sessions and disrupting routing services until the process restarts.","summary":"On affected Arista EOS-based network platforms, a peer that controls a BGP session with the Dynamic Path Selection address family can send a crafted BGP message. This terminates the BGP process, resetting all BGP sessions and disrupting routing until the process restarts.","severity":"medium","cvss":6.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["arista-eos","bgp","infrastructure","network-devices"],"not_affected_if":["no-dps-address-family","no-untrusted-bgp-peers"],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T20:18:55+00:00","first_seen_at":"2026-11-10T20:46:03+00:00","triaged_at":"2026-11-10T20:47:59+00:00","updated_at":"2026-11-10T20:47:59+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-11-10T20:47:59Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"Arista EOS: crafted BGP message crashes routing process and resets sessions","impact":"medium","summary":"On affected Arista EOS-based network platforms, a peer that controls a BGP session with the Dynamic Path Selection address family can send a crafted BGP message. This terminates the BGP process, resetting all BGP sessions and disrupting routing until the process restarts.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["arista-eos","bgp","network-devices"],"confidence":0.6,"fix_status":"unknown","needs_auth":"yes","worst_case":"BGP process crashes, resetting all sessions and disrupting routing","analyst_note":"Find the affected EOS versions and fixed releases in the Arista security advisory; the NVD entry does not list them.","how_to_check":"unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["no-dps-address-family","no-untrusted-bgp-peers"],"who_is_affected":"Network operators running EOS-based switches or routers that peer over BGP with the Dynamic Path Selection address family negotiated. An attacker must control a BGP peer, so exposure depends on who can establish sessions with the device. Devices without DPS negotiated, or without untrusted BGP peers, are less exposed. The sources do not list affected EOS versions.","user_interaction":"no","product_ecosystem":"vendor","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000726,"input_tokens":4580,"output_tokens":536,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-121293':14A,17A '-2026':13A,16A 'address':46B,102C 'affect':27B,71C 'arista':1A,19B,28B 'arista-eo':18B 'attack':77C 'base':31B,74C 'bgp':4A,21B,39B,52B,57B,61B,84C,90C,109C,116C 'border':81C 'caus':107C 'control':37B,79C 'craft':3A,51B,89C 'crash':6A 'cve':12A,15A 'devic':25B 'disrupt':64B,119C 'dps':101C 'dynam':43B,98C 'eo':2A,20B,30B,73C 'eos-bas':29B,72C 'establish':94C 'famili':47B,103C 'gateway':82C 'infrastructur':22B 'messag':5A,53B,91C 'negoti':104C 'network':24B,32B 'network-devic':23B 'path':44B,99C 'peer':35B,85C 'platform':33B,75C 'process':8A,58B,68B,110C,124C 'protocol':83C 'reset':10A,59B,114C 'restart':69B,125C 'rout':7A,65B,120C 'select':45B,100C 'send':49B,87C 'servic':121C 'session':11A,40B,62B,95C,117C 'termin':55B,112C 'unexpect':113C","nicknames":[],"mitigations":[],"who_affected":"Network operators running EOS-based switches or routers that peer over BGP with the Dynamic Path Selection address family negotiated. An attacker must control a BGP peer, so exposure depends on who can establish sessions with the device. Devices without DPS negotiated, or without untrusted BGP peers, are less exposed. The sources do not list affected EOS versions.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["aristaeos","bgp","infrastructure","medium","networkdevices"],"campaign_type":null,"search_a":"'-121293':14A,17A '-2026':13A,16A 'arista':1A 'bgp':4A 'craft':3A 'crash':6A 'cve':12A,15A 'eo':2A 'messag':5A 'process':8A 'reset':10A 'rout':7A 'session':11A","search_b":"'address':46B 'affect':27B 'arista':19B,28B 'arista-eo':18B 'base':31B 'bgp':21B,39B,52B,57B,61B 'control':37B 'craft':51B 'devic':25B 'disrupt':64B 'dynam':43B 'eo':20B,30B 'eos-bas':29B 'famili':47B 'infrastructur':22B 'messag':53B 'network':24B,32B 'network-devic':23B 'path':44B 'peer':35B 'platform':33B 'process':58B,68B 'reset':59B 'restart':69B 'rout':65B 'select':45B 'send':49B 'session':40B,62B 'termin':55B","search_c":"'address':102C 'affect':71C 'attack':77C 'base':74C 'bgp':84C,90C,109C,116C 'border':81C 'caus':107C 'control':79C 'craft':89C 'disrupt':119C 'dps':101C 'dynam':98C 'eo':73C 'eos-bas':72C 'establish':94C 'famili':103C 'gateway':82C 'messag':91C 'negoti':104C 'path':99C 'peer':85C 'platform':75C 'process':110C,124C 'protocol':83C 'reset':114C 'restart':125C 'rout':120C 'select':100C 'send':87C 'servic':121C 'session':95C,117C 'termin':112C 'unexpect':113C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T20:18:55+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:H/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":"psirt@arista.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121293","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121293","severity":null,"published_at":"2026-11-10T20:18:55+00:00","modified_at":"2026-11-10T20:18:55+00:00","first_seen_at":"2026-11-10T20:46:03+00:00","fetched_at":"2026-11-10T20:46:03+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}