{"id":"CVE-2026-98561","kind":"vulnerability","aliases":["CVE-2026-98561"],"related":[],"title":"Linux kernel nfp driver: IPsec RX use-after-free race on state refcount","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfp: hold IPsec RX state under the XArray lock\n\nnfp_net_ipsec_rx() drops the XArray lock before taking a reference to the\nxfrm_state it found. The delete path can erase the entry and drop the last\nstate reference in that interval. RX can then try to increment a zero\nrefcount after the state has been queued for destruction.\n\nThe driver queues firmware invalidation asynchronously; the delete path\ndoes not wait for the command to complete or drain pending RX processing.\n\nThe XFRM garbage collector waits for an RCU grace period before freeing\nthe state. That delays reclamation but does not make acquiring a reference\nfrom zero valid.\n\nTake the xfrm_state reference before releasing the XArray lock so\nxa_erase() cannot run between lookup and reference acquisition.","summary":"In the Linux kernel's nfp Netronome network driver, the IPsec receive path could take a reference to an xfrm_state after it had been queued for destruction, a refcount race. The sources do not state what an attacker gets at worst.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","ipsec","linux-kernel","nfp-driver","smartnic"],"not_affected_if":["no-ipsec-offload","no-nfp-hardware"],"how_to_check":"- unknown","fix":"- Update to a Linux kernel release that includes the upstream commit resolving the nfp IPsec RX state locking; the sources do not name a fixed version.","status":"open","published_at":"2026-10-18T16:17:08+00:00","first_seen_at":"2026-10-23T21:57:15+00:00","triaged_at":"2026-10-25T05:23:23+00:00","updated_at":"2026-10-25T05:23:23+00:00","category":"infrastructure","confidence":0.4,"triage":{"at":"2026-10-25T05:23:23Z","model":"claude-haiku-5-5","output":{"fix":"- Update to a Linux kernel release that includes the upstream commit resolving the nfp IPsec RX state locking; the sources do not name a fixed version.","reach":"network","title":"Linux kernel nfp driver: IPsec RX use-after-free race on state refcount","impact":"medium","summary":"In the Linux kernel's nfp Netronome network driver, the IPsec receive path could take a reference to an xfrm_state after it had been queued for destruction, a refcount race. The sources do not state what an attacker gets at worst.","category":"infrastructure","nicknames":[],"who_cares":["linux-kernel","nfp-driver","ipsec","smartnic"],"confidence":0.4,"needs_auth":"unknown","worst_case":"unknown","analyst_note":"Check the NVD entry and the upstream kernel commit for the exploit impact, affected kernel version range and fixed versions.","how_to_check":"- unknown","needs_analyst":true,"not_affected_if":["no-nfp-hardware","no-ipsec-offload"],"who_is_affected":"Systems running a Linux kernel with the nfp driver (Netronome/Corigine SmartNIC hardware) and IPsec offload enabled are the ones this race applies to. Hosts without that NIC or without IPsec offload are unlikely to be exposed. The sources do not say more.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"unknown"},"cost_usd":0.0006,"input_tokens":3494,"output_tokens":502,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':16A,19A '-98561':17A,20A 'acquir':185C 'acquisit':210C 'asynchron':147C 'attack':68B 'cannot':204C 'collector':167C 'command':156C 'complet':158C 'could':43B 'cve':15A,18A 'delay':179C 'delet':110C,149C 'destruct':57B,141C 'drain':160C 'driver':4A,28B,38B,143C 'drop':95C,117C 'entri':115C 'eras':113C,203C 'firmwar':145C 'follow':77C 'found':108C 'free':10A,175C 'garbag':166C 'get':69B 'grace':172C 'hold':83C 'increment':130C 'infrastructur':21B 'interv':124C 'invalid':146C 'ipsec':5A,22B,40B,84C,93C 'kernel':2A,25B,33B,75C 'last':119C 'linux':1A,24B,32B,74C 'linux-kernel':23B 'lock':90C,98C,200C 'lookup':207C 'make':184C 'net':92C 'netronom':36B 'network':37B 'nfp':3A,27B,35B,82C,91C 'nfp-driver':26B 'path':42B,111C,150C 'pend':161C 'period':173C 'process':163C 'queu':55B,139C 'queue':144C 'race':11A,60B 'rcu':171C 'receiv':41B 'reclam':180C 'refcount':14A,59B,133C 'refer':46B,102C,121C,187C,195C,209C 'releas':197C 'resolv':81C 'run':205C 'rx':6A,85C,94C,125C,162C 'smartnic':29B 'sourc':62B 'state':13A,50B,65B,86C,106C,120C,136C,177C,194C 'take':44B,100C,191C 'tri':128C 'use':8A 'use-after-fre':7A 'valid':190C 'vulner':78C 'wait':153C,168C 'worst':71B 'xa':202C 'xarray':89C,97C,199C 'xfrm':49B,105C,165C,193C 'zero':132C,189C","nicknames":[],"mitigations":[],"who_affected":"Systems running a Linux kernel with the nfp driver (Netronome/Corigine SmartNIC hardware) and IPsec offload enabled are the ones this race applies to. Hosts without that NIC or without IPsec offload are unlikely to be exposed. The sources do not say more.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-18T16:17:08+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-98561","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98561","severity":null,"published_at":"2026-10-18T16:17:08+00:00","modified_at":"2026-10-19T10:19:12+00:00","first_seen_at":"2026-10-23T21:57:15+00:00","fetched_at":"2026-10-23T22:28:56+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"}