{"id":"CVE-2026-20499","kind":"vulnerability","aliases":["CVE-2026-20499"],"related":[],"title":"Modem firmware: out-of-bounds write lets a rogue base station take over","description":"In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote escalation of privilege, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01857954; Issue ID: MSV-8247.","summary":"A missing bounds check in the modem firmware allows an out-of-bounds write. A phone or device that connects to an attacker-controlled rogue base station can be exploited to escalate privileges remotely, without user interaction.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["cellular","infrastructure","mobile","modem"],"not_affected_if":["unknown"],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-02T03:17:31+00:00","first_seen_at":"2026-11-02T03:31:23+00:00","triaged_at":"2026-11-02T03:34:02+00:00","updated_at":"2026-11-02T03:34:02+00:00","category":"infrastructure","confidence":0.5,"triage":{"at":"2026-11-02T03:34:02Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"Modem firmware: out-of-bounds write lets a rogue base station take over","impact":"high","summary":"A missing bounds check in the modem firmware allows an out-of-bounds write. A phone or device that connects to an attacker-controlled rogue base station can be exploited to escalate privileges remotely, without user interaction.","audience":"everyone","category":"infrastructure","nicknames":[],"who_cares":["modem","cellular","mobile"],"confidence":0.5,"fix_status":"unknown","needs_auth":"no","worst_case":"Remote privilege escalation on a device that connects to a rogue base station","analyst_note":"Find the affected device list and patch level from the vendor bulletin for Patch ID MOLY01857954 / Issue ID MSV-8247.","how_to_check":"- unknown","plain_action":"unknown","needs_analyst":true,"not_affected_if":["unknown"],"who_is_affected":"Devices with the affected modem firmware that connect to cellular networks can be exposed if they connect to a rogue base station. The sources do not list the affected devices or modem versions. Teams running fleets of phones or IoT devices with cellular modems should check with their device vendor.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000642,"input_tokens":4122,"output_tokens":459,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-20499':16A,19A '-8247':120C 'addit':103C 'allow':32B 'attack':48B,100C 'attacker-control':47B 'base':11A,51B,95C 'bound':6A,26B,37B,71C,77C 'cellular':20B 'check':27B,78C 'connect':44B,91C 'control':49B,97C 'could':80C 'cve':14A,17A 'devic':42B 'due':73C 'escal':57B,84C 'execut':104C 'exploit':55B,113C 'firmwar':2A,31B 'id':115C,118C 'infrastructur':21B 'interact':62B,108C 'issu':117C 'lead':81C 'let':8A 'miss':25B,76C 'mobil':22B 'modem':1A,23B,30B,64C 'moly01857954':116C 'msv':119C 'need':106C,111C 'out-of-bound':3A,34B 'patch':114C 'phone':40B 'possibl':68C 'privileg':58B,86C,105C 'remot':59B,83C 'rogu':10A,50B,94C 'station':12A,52B,96C 'take':13A 'ue':89C 'user':61B,107C 'without':60B 'write':7A,38B,72C","nicknames":[],"mitigations":[],"who_affected":"Devices with the affected modem firmware that connect to cellular networks can be exposed if they connect to a rogue base station. The sources do not list the affected devices or modem versions. Teams running fleets of phones or IoT devices with cellular modems should check with their device vendor.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"unknown","audience":"everyone","plain_action":null,"pkeys":[],"ptokens":[],"labels":["cellular","infrastructure","mobile","modem","unknown"],"first_public_at":"2026-11-02T03:17:31+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-20499","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20499","severity":null,"published_at":"2026-11-02T03:17:31+00:00","modified_at":"2026-11-02T03:17:31+00:00","first_seen_at":"2026-11-02T03:31:23+00:00","fetched_at":"2026-11-02T03:31:23+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"}