{"id":"CVE-2026-103653","kind":"vulnerability","aliases":["CVE-2026-103653"],"related":[],"title":"Qt CoAP: malformed message parsing reads out of bounds, crashing apps","description":"An out-of-bounds read vulnerability in the Qt CoAP message parsing (QCoapInternalReply::createFromFrame()) of the Qt CoAP module. Processing a malformed CoAP message can cause an application using Qt CoAP to crash (loss of availability) or to continue operating on incorrect data (potential loss of integrity).","summary":"The Qt CoAP module reads past the end of a buffer when it parses a malformed CoAP message in QCoapInternalReply::createFromFrame(). An attacker who sends such a message can crash an application using Qt CoAP or make it act on incorrect data.","severity":"medium","cvss":6.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["c++","coap","package","qt"],"not_affected_if":["no-qt-coap-module"],"how_to_check":"- Check whether an application links the Qt CoAP module (look for `Qt6CoAP` or `Qt5CoAP` in build files or dependencies).\n- Check the installed Qt version with `qmake --version` or `qt-cmake --version`; the affected and fixed version ranges are unknown from the sources.","fix":null,"status":"open","published_at":"2026-11-03T08:17:13+00:00","first_seen_at":"2026-11-03T08:19:30+00:00","triaged_at":"2026-11-03T08:19:37+00:00","updated_at":"2026-11-03T08:19:37+00:00","category":"package","confidence":0.5,"triage":{"at":"2026-11-03T08:19:37Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"Qt CoAP: malformed message parsing reads out of bounds, crashing apps","impact":"medium","summary":"The Qt CoAP module reads past the end of a buffer when it parses a malformed CoAP message in QCoapInternalReply::createFromFrame(). An attacker who sends such a message can crash an application using Qt CoAP or make it act on incorrect data.","audience":"developers","category":"package","nicknames":[],"who_cares":["qt","coap","c++"],"confidence":0.5,"fix_status":"unknown","needs_auth":"unknown","worst_case":"Application crashes or continues on corrupted data","analyst_note":"Find the affected and fixed Qt versions and any vendor advisory for CVE-2026-103653 in the Qt project security pages; the NVD entry alone gives no version ranges.","how_to_check":"- Check whether an application links the Qt CoAP module (look for `Qt6CoAP` or `Qt5CoAP` in build files or dependencies).\n- Check the installed Qt version with `qmake --version` or `qt-cmake --version`; the affected and fixed version ranges are unknown from the sources.","plain_action":"","needs_analyst":true,"not_affected_if":["no-qt-coap-module"],"who_is_affected":"Applications built with the Qt CoAP module that receive CoAP messages, including over a network, are exposed to a crash or incorrect data. Applications that do not use Qt CoAP are not affected. The sources do not give affected version ranges.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.0007,"input_tokens":4154,"output_tokens":570,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-103653':14A,17A '-2026':13A,16A 'act':60B 'app':11A 'applic':53B,92C 'attack':44B 'avail':100C 'bound':9A,68C 'buffer':32B 'c':18B 'caus':90C 'coap':2A,19B,24B,38B,56B,74C,82C,87C,95C 'continu':103C 'crash':10A,51B,97C 'createfromfram':42B,78C 'cve':12A,15A 'data':63B,107C 'end':29B 'incorrect':62B,106C 'integr':111C 'loss':98C,109C 'make':58B 'malform':3A,37B,86C 'messag':4A,39B,49B,75C,88C 'modul':25B,83C 'oper':104C 'out-of-bound':65C 'packag':20B 'pars':5A,35B,76C 'past':27B 'potenti':108C 'process':84C 'qcoapinternalrepli':41B,77C 'qt':1A,21B,23B,55B,73C,81C,94C 'read':6A,26B,69C 'send':46B 'use':54B,93C 'vulner':70C","nicknames":[],"mitigations":[],"who_affected":"Applications built with the Qt CoAP module that receive CoAP messages, including over a network, are exposed to a crash or incorrect data. Applications that do not use Qt CoAP are not affected. The sources do not give affected version ranges.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"developers","plain_action":null,"pkeys":[],"ptokens":[],"labels":["c","coap","medium","package","qt"],"first_public_at":"2026-11-03T08:17:13+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:U/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:Y/R:U/V:X/RE:L/U:Amber","cvss_by":"a59d8014-47c4-4630-ab43-e1b13cbe58e3","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-103653","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-103653","severity":null,"published_at":"2026-11-03T08:17:13+00:00","modified_at":"2026-11-03T08:17:13+00:00","first_seen_at":"2026-11-03T08:19:30+00:00","fetched_at":"2026-11-03T08:19:30+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"}