{"id":"CVE-2026-103672","kind":"vulnerability","aliases":["CVE-2026-103672"],"related":[],"title":"PEAK-System PCAN parser: unchecked DLC overflows a stack buffer","description":"The PEAK-System PCAN parser indexes a length table using attacker-controlled DLC without enforcing DLC <= 0x0f, then copies attacker payload from record+0x1c into a fixed-size stack destination.","summary":"The PEAK-System PCAN parser uses an attacker-supplied DLC value to index a length table without checking that it is 0x0f or less. The payload is then copied into a fixed-size stack buffer, which can overflow and may let an attacker run code.","severity":"high","cvss":7.1,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"PEAK-System Device Driver Setup","fixed":["5.1.4"],"affected":"<= 5.1.2.1151","ecosystem":"vendor"},{"name":"PCAN Windows CAN device drivers","fixed":["5.1.4"],"affected":"<= 5.1.2","ecosystem":"vendor"}],"ecosystems":[],"tags":["can-bus","hms-networks","ics","infrastructure","kernel-driver","local","pcan","peak-system","windows"],"not_affected_if":["linux","no-pcan-driver-installed","version-5.1.4-or-later"],"how_to_check":"On Windows, check the installed PEAK-System Device Driver Setup version (Programs and Features) and the PCAN driver version in Device Manager. Affected if Setup <= 5.1.2.1151 or PCAN driver <= 5.1.2; 5.1.4 is fixed.","fix":"Upgrade to PEAK-System PCAN Windows driver / Device Driver Setup 5.1.4 or newer (https://www.peak-system.com/support/downloads/software/).","status":"open","published_at":"2026-10-20T21:17:14+00:00","first_seen_at":"2026-10-23T21:57:21+00:00","triaged_at":"2026-10-25T03:34:34+00:00","updated_at":"2026-10-25T03:35:55+00:00","category":"infrastructure","confidence":0.75,"triage":{"at":"2026-10-25T03:34:34Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"unknown","title":"PEAK-System PCAN parser: unchecked DLC overflows a stack buffer","impact":"high","summary":"The PEAK-System PCAN parser uses an attacker-supplied DLC value to index a length table without checking that it is 0x0f or less. The payload is then copied into a fixed-size stack buffer, which can overflow and may let an attacker run code.","category":"infrastructure","nicknames":[],"who_cares":["peak-system","pcan","can-bus"],"confidence":0.4,"needs_auth":"unknown","worst_case":"Stack overflow in parser could allow code execution","analyst_note":"Find the affected PCAN driver or library versions and the vendor advisory in the NVD entry (https://nvd.nist.gov/vuln/detail/CVE-2026-103672).","how_to_check":"unknown","needs_analyst":true,"not_affected_if":[],"who_is_affected":"unknown","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000517,"input_tokens":3300,"output_tokens":374,"severity_before":"high"},"analyst_status":"done","analyst_note":"Find the affected PCAN driver or library versions and the vendor advisory in the NVD entry (https://nvd.nist.gov/vuln/detail/CVE-2026-103672).","search":"'+0':119C '-103672':14A,17A '-2026':13A,16A '0x0f':69B,112C 'attack':55B,91B,106C,115C 'attacker-control':105C 'attacker-suppli':54B 'buffer':11A,83B 'bus':31B 'can':26A 'can-bus':29B 'check':65B 'code':93B 'control':107C 'copi':76B,114C 'cve':12A,15A 'destin':127C 'device':21A,27A 'dlc':7A,57B,108C,111C 'driver':22A,39B 'drivers':28A 'enforc':110C 'fix':80B,124C 'fixed-s':79B,123C 'hms':33B 'hms-network':32B 'ic':35B 'index':60B,100C 'infrastructur':36B 'kernel':38B 'kernel-driv':37B 'length':62B,102C 'less':71B 'let':89B 'local':40B 'may':88B 'network':34B 'overflow':8A,86B 'parser':5A,51B,99C 'payload':73B,116C 'pcan':4A,24A,41B,50B,98C 'peak':2A,19A,43B,48B,96C 'peak-system':1A,18A,42B,47B,95C 'record':118C 'run':92B 'setup':23A 'size':81B,125C 'stack':10A,82B,126C 'suppli':56B 'system':3A,20A,44B,49B,97C 'tabl':63B,103C 'uncheck':6A 'use':52B,104C 'valu':58B 'window':45B 'windows':25A 'without':64B,109C 'x1c':120C","nicknames":[],"mitigations":[],"who_affected":null,"tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T21:17:14+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/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":"ics-cert@hq.dhs.gov","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-103672","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-103672","severity":null,"published_at":"2026-10-20T21:17:14+00:00","modified_at":"2026-10-22T17:36:46+00:00","first_seen_at":"2026-10-23T21:57:21+00:00","fetched_at":"2026-10-23T22:28:58+00:00","note":null},{"source":"analyst","external_id":"CVE-2026-103672:750","url":null,"severity":null,"published_at":"2026-10-25T03:35:55+00:00","modified_at":"2026-10-25T03:35:55+00:00","first_seen_at":"2026-10-25T03:35:55+00:00","fetched_at":"2026-10-25T03:35:55+00:00","note":"CISA ICSA-26-293-01 (republishing HMS Networks CSAF): affects PEAK-System Device Driver Setup <=5.1.2.1151 and PCAN Windows drivers <=5.1.2; fixed in 5.1.4. Local low-priv, kernel driver stack overflow (CWE-129); no exploitation or PoC seen; did not read HMS's own advisory page, so nothing marked verified. Social search skipped (no public conversation expected)."}],"documents":[{"id":3241,"url":"https://www.cisa.gov/news-events/ics-advisories/icsa-26-293-01","title":"CISA ICSA-26-293-01 HMS Networks PEAK-System PCAN Windows drivers","kind":"advisory","source":"analyst","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":null},{"id":3242,"url":"https://app.opencve.io/cve/CVE-2026-103672","title":"OpenCVE CVE-2026-103672","kind":"other","source":"analyst","text":null,"published_at":null,"relation":"mentions","confidence":null,"note":null}],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}