{"id":"CVE-2026-28248","kind":"vulnerability","aliases":["CVE-2026-28248"],"related":[],"title":"AMD SEV firmware: malicious hypervisor can launch guests with forged attestation","description":"Improper enforcement of behavioral workflow in AMD Secure Encrypted Virtualization (SEV) firmware could allow a malicious hypervisor to potentially launch a guest whose attestation report contains an ID key digest for an ID block that doesn't match the guest's measurement resulting in loss of integrity.","summary":"AMD Secure Encrypted Virtualization firmware fails to enforce a required workflow, so a malicious hypervisor can launch a guest whose attestation report carries an ID key digest that does not match the guest's measurement. The result is loss of integrity for the guest.","severity":"medium","cvss":5.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["amd","confidential-computing","hypervisor","infrastructure","sev"],"not_affected_if":["no-amd-sev","non-confidential-guests"],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T22:18:32+00:00","first_seen_at":"2026-11-10T22:27:30+00:00","triaged_at":"2026-11-10T22:29:21+00:00","updated_at":"2026-11-10T22:29:21+00:00","category":"infrastructure","confidence":0.5,"triage":{"at":"2026-11-10T22:29:21Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"AMD SEV firmware: malicious hypervisor can launch guests with forged attestation","impact":"medium","summary":"AMD Secure Encrypted Virtualization firmware fails to enforce a required workflow, so a malicious hypervisor can launch a guest whose attestation report carries an ID key digest that does not match the guest's measurement. The result is loss of integrity for the guest.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["amd","sev","confidential-computing","hypervisor"],"confidence":0.5,"fix_status":"unknown","needs_auth":"unknown","worst_case":"Guest integrity lost through a forged attestation report from a malicious hypervisor","analyst_note":"Find AMD's security bulletin for CVE-2026-28248 to get affected firmware versions, fixed versions and mitigation steps; the NVD entry alone gives none.","how_to_check":"- unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["no-amd-sev","non-confidential-guests"],"who_is_affected":"Affects hosts running AMD SEV confidential computing guests where the hypervisor could be malicious or compromised. The sources do not name affected firmware versions or products, so the exposed set is unknown. Teams not running AMD SEV guests on AMD hardware can likely skip it.","user_interaction":"no","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000718,"input_tokens":4565,"output_tokens":522,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-28248':14A,17A 'allow':82C 'amd':1A,18B,25B,75C 'attest':11A,45B,92C 'behavior':72C 'block':102C 'carri':47B 'comput':21B 'confidenti':20B 'confidential-comput':19B 'contain':94C 'could':81C 'cve':12A,15A 'digest':51B,98C 'doesn':104C 'encrypt':27B,77C 'enforc':32B,70C 'fail':30B 'firmwar':3A,29B,80C 'forg':10A 'guest':8A,43B,57B,68B,90C,108C 'hypervisor':5A,22B,39B,85C 'id':49B,96C,101C 'improp':69C 'infrastructur':23B 'integr':65B,115C 'key':50B,97C 'launch':7A,41B,88C 'loss':63B,113C 'malici':4A,38B,84C 'match':55B,106C 'measur':59B,110C 'potenti':87C 'report':46B,93C 'requir':34B 'result':61B,111C 'secur':26B,76C 'sev':2A,24B,79C 'virtual':28B,78C 'whose':44B,91C 'workflow':35B,73C","nicknames":[],"mitigations":[],"who_affected":"Affects hosts running AMD SEV confidential computing guests where the hypervisor could be malicious or compromised. The sources do not name affected firmware versions or products, so the exposed set is unknown. Teams not running AMD SEV guests on AMD hardware can likely skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"unknown","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["amd","confidentialcomputing","hypervisor","infrastructure","medium","sev"],"campaign_type":null,"search_a":"'-2026':13A,16A '-28248':14A,17A 'amd':1A 'attest':11A 'cve':12A,15A 'firmwar':3A 'forg':10A 'guest':8A 'hypervisor':5A 'launch':7A 'malici':4A 'sev':2A","search_b":"'amd':18B,25B 'attest':45B 'carri':47B 'comput':21B 'confidenti':20B 'confidential-comput':19B 'digest':51B 'encrypt':27B 'enforc':32B 'fail':30B 'firmwar':29B 'guest':43B,57B,68B 'hypervisor':22B,39B 'id':49B 'infrastructur':23B 'integr':65B 'key':50B 'launch':41B 'loss':63B 'malici':38B 'match':55B 'measur':59B 'report':46B 'requir':34B 'result':61B 'secur':26B 'sev':24B 'virtual':28B 'whose':44B 'workflow':35B","search_c":"'allow':82C 'amd':75C 'attest':92C 'behavior':72C 'block':102C 'contain':94C 'could':81C 'digest':98C 'doesn':104C 'encrypt':77C 'enforc':70C 'firmwar':80C 'guest':90C,108C 'hypervisor':85C 'id':96C,101C 'improp':69C 'integr':115C 'key':97C 'launch':88C 'loss':113C 'malici':84C 'match':106C 'measur':110C 'potenti':87C 'report':93C 'result':111C 'secur':76C 'sev':79C 'virtual':78C 'whose':91C 'workflow':73C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T22:18:32+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/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":"psirt@amd.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-28248","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-28248","severity":null,"published_at":"2026-11-10T22:18:32+00:00","modified_at":"2026-11-10T22:18:32+00:00","first_seen_at":"2026-11-10T22:27:30+00:00","fetched_at":"2026-11-10T22:27:30+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"}