{"id":"CVE-2026-107858","kind":"vulnerability","aliases":["CVE-2026-107858"],"related":[],"title":"Google ADK dev web server: any website can control local agents","description":"Missing Origin Validation in WebSockets (CWE-1385) and Permissive Cross-domain Policy with Untrusted Domains (CWE-942) in the development web server (ADK Web) in Google Agent Development Kit (ADK) for Java (com.google.adk:google-adk-dev versions 0.1.0 before 1.13.0 and com.google.adk:google-adk-maven-plugin versions 0.3.0 before 1.13.0) allow a remote attacker to control a locally running agent and read its data via a malicious web page visited by a developer while the server is running. The /run_live WebSocket endpoint accepts connections from any origin by default (hardcoded via setAllowedOrigins(\"*\") in versions 0.1.0 through 1.5.0, and defaulting to * via adk.web.cors.origins in versions 1.6.0 through 1.12.0), and since version 0.4.0 the REST API returns Access-Control-Allow-Origin: * by default. Because the server has no authentication and requests originate from the developer's browser (so binding to localhost does not prevent exploitation), a cross-origin page can send messages to the agent (triggering registered tools), stream agent responses, and list, read, create, or delete sessions and artifacts. In versions 1.6.0 through 1.12.0, users can mitigate the issue by setting the adk.web.cors.origins property to an explicit allowlist of trusted origins (such as http://localhost:8000). The vulnerability is fixed in version 1.13.0, which enforces a same-origin default for CORS and the /run_live WebSocket endpoint, and rejects DNS-rebinding requests over loopback.","summary":"The ADK development web server in Google Agent Development Kit for Java accepts WebSocket and cross-origin requests from any website, with no authentication. A malicious page open in a developer's browser while the server runs can send messages to the agent, trigger its tools, and read or change its sessions and artifacts.","severity":"high","cvss":7.2,"epss":0.0036,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ai-agents","ai-tooling","developer-machines","google-adk","java"],"not_affected_if":["dev-server-not-running","production-only","version-1.13.0-or-later"],"how_to_check":"- Check the Maven dependency for `com.google.adk:google-adk-dev` and `com.google.adk:google-adk-maven-plugin` and note the version.\n- Confirm whether the ADK web server (`adk web` or the dev server) was started on the machine, and whether `adk.web.cors.origins` is set in the configuration.","fix":"- Upgrade `com.google.adk:google-adk-dev` and `com.google.adk:google-adk-maven-plugin` to `1.13.0` or later.\n- On versions `1.6.0` through `1.12.0`, set `adk.web.cors.origins` to an explicit allowlist such as `http://localhost:8000`.","status":"open","published_at":"2026-10-23T06:17:03+00:00","first_seen_at":"2026-10-23T21:57:32+00:00","triaged_at":"2026-10-25T03:27:46+00:00","updated_at":"2026-10-25T03:27:46+00:00","category":"ai-tooling","confidence":0.8,"triage":{"at":"2026-10-25T03:27:46Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade `com.google.adk:google-adk-dev` and `com.google.adk:google-adk-maven-plugin` to `1.13.0` or later.\n- On versions `1.6.0` through `1.12.0`, set `adk.web.cors.origins` to an explicit allowlist such as `http://localhost:8000`.","reach":"internet","title":"Google ADK dev web server: any website can control local agents","impact":"high","summary":"The ADK development web server in Google Agent Development Kit for Java accepts WebSocket and cross-origin requests from any website, with no authentication. A malicious page open in a developer's browser while the server runs can send messages to the agent, trigger its tools, and read or change its sessions and artifacts.","category":"ai-tooling","nicknames":[],"who_cares":["java","google-adk","ai-agents","developer-machines"],"confidence":0.8,"needs_auth":"no","worst_case":"Remote page controls local agent, triggers tools, reads sessions and artifacts","analyst_note":"","how_to_check":"- Check the Maven dependency for `com.google.adk:google-adk-dev` and `com.google.adk:google-adk-maven-plugin` and note the version.\n- Confirm whether the ADK web server (`adk web` or the dev server) was started on the machine, and whether `adk.web.cors.origins` is set in the configuration.","needs_analyst":false,"not_affected_if":["version-1.13.0-or-later","dev-server-not-running","production-only"],"who_is_affected":"Developers running the ADK development web server (the dev-only server, not a production deployment) from the Java package versions listed. Exposure comes from a developer browsing a malicious page while the server is running; binding to localhost does not prevent it because requests come from the developer's own browser. Teams that do not run the dev web server, or that run only on versions 1.13.0 and later, can skip it.","user_interaction":"yes","needs_special_setup":"yes","severity_if_unknown":"high"},"cost_usd":0.000723,"input_tokens":3815,"output_tokens":684,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-107858':14A,17A '-1385':92C '-2026':13A,16A '-942':103C '/run_live':168C,303C '0.1.0':125C,183C '0.3.0':136C '0.4.0':199C '1.12.0':195C,263C '1.13.0':127C,138C,291C '1.5.0':185C '1.6.0':193C,261C '8000':284C 'accept':43B,171C 'access':205C 'access-control-allow-origin':204C 'adk':2A,29B,32B,109C,116C,122C,132C 'adk.web.cors.origins':190C,272C 'agent':11A,20B,38B,74B,113C,148C,243C,248C 'ai':19B,22B 'ai-ag':18B 'ai-tool':21B 'allow':139C,207C 'allowlist':277C 'api':202C 'artifact':85B,258C 'attack':142C 'authent':55B,216C 'bind':226C 'browser':64B,224C 'chang':81B 'com.google.adk':119C,129C 'connect':172C 'control':9A,144C,206C 'cor':300C 'creat':253C 'cross':47B,96C,235C 'cross-domain':95C 'cross-origin':46B,234C 'cve':12A,15A 'cwe':91C,102C 'data':152C 'default':177C,187C,210C,298C 'delet':255C 'dev':3A,123C 'develop':25B,33B,39B,62B,106C,114C,161C,222C 'developer-machin':24B 'dns':309C 'dns-rebind':308C 'domain':97C,101C 'endpoint':170C,305C 'enforc':293C 'explicit':276C 'exploit':232C 'fix':288C 'googl':1A,28B,37B,112C,121C,131C 'google-adk':27B 'google-adk-dev':120C 'google-adk-maven-plugin':130C 'hardcod':178C 'issu':268C 'java':30B,42B,118C 'kit':40B,115C 'list':251C 'local':10A,146C 'localhost':228C,283C 'loopback':313C 'machin':26B 'malici':57B,155C 'maven':133C 'messag':71B,240C 'miss':86C 'mitig':266C 'open':59B 'origin':48B,87C,175C,208C,219C,236C,280C,297C 'page':58B,157C,237C 'permiss':94C 'plugin':134C 'polici':98C 'prevent':231C 'properti':273C 'read':79B,150C,252C 'rebind':310C 'regist':245C 'reject':307C 'remot':141C 'request':49B,218C,311C 'respons':249C 'rest':201C 'return':203C 'run':68B,147C,166C 'same-origin':295C 'send':70B,239C 'server':5A,35B,67B,108C,164C,213C 'session':83B,256C 'set':270C 'setallowedorigin':180C 'sinc':197C 'stream':247C 'tool':23B,77B,246C 'trigger':75B,244C 'trust':279C 'untrust':100C 'user':264C 'valid':88C 'version':124C,135C,182C,192C,198C,260C,290C 'via':153C,179C,189C 'visit':158C 'vulner':286C 'web':4A,34B,107C,110C,156C 'websit':7A,52B 'websocket':44B,90C,169C,304C","nicknames":[],"mitigations":[],"who_affected":"Developers running the ADK development web server (the dev-only server, not a production deployment) from the Java package versions listed. Exposure comes from a developer browsing a malicious page while the server is running; binding to localhost does not prevent it because requests come from the developer's own browser. Teams that do not run the dev web server, or that run only on versions 1.13.0 and later, can skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-23T06:17:03+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:L/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":"cve-coordination@google.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-107858","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-107858","severity":null,"published_at":"2026-10-23T06:17:03+00:00","modified_at":"2026-10-23T19:42:24+00:00","first_seen_at":"2026-10-23T21:57:32+00:00","fetched_at":"2026-10-23T22:29:03+00:00","note":null},{"source":"epss","external_id":"CVE-2026-107858","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-107858","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-24T07:15:51+00:00","fetched_at":"2026-10-24T07:15:51+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"}