{"id":"CVE-2026-119121","kind":"vulnerability","aliases":["CVE-2026-119121"],"related":[],"title":"Crawl4AI: authenticated API users can run JavaScript in crawled pages","description":"Crawl4AI from 0.9.0 before 0.9.5 contains a JavaScript injection vulnerability in the Docker API server that allows authenticated API clients to run arbitrary JavaScript in the crawl page via allowlisted css_selector and wait_for fields. Attackers can inject quotes into css_selector or supply js: conditions in wait_for, bypassing the js_code block to alter page state and returned crawl content.","summary":"Crawl4AI versions from 0.9.0 before 0.9.5 let an authenticated client of the Docker API server inject JavaScript through the css_selector and wait_for fields. The injected script runs in the crawled page, so an attacker can alter page state and the content the crawl returns.","severity":"medium","cvss":5.3,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ai-tooling","crawl4ai","docker","python"],"not_affected_if":["api-server-not-deployed","library-only-use","version-0.9.5-or-later"],"how_to_check":"- Check the installed Crawl4AI version, for example with `pip show crawl4ai` or the image tag of the Docker deployment.\n- Confirm whether the Docker API server is reachable by clients outside your trusted group.","fix":"- Crawl4AI `0.9.5` or later, per the advisory's fixed range (from 0.9.0 before 0.9.5 is affected).","status":"open","published_at":"2026-10-29T16:18:04+00:00","first_seen_at":"2026-10-29T16:25:58+00:00","triaged_at":"2026-10-29T16:31:53+00:00","updated_at":"2026-10-29T16:31:53+00:00","category":"ai-tooling","confidence":0.6,"triage":{"at":"2026-10-29T16:31:53Z","model":"claude-haiku-5-5","output":{"fix":"- Crawl4AI `0.9.5` or later, per the advisory's fixed range (from 0.9.0 before 0.9.5 is affected).","reach":"network","title":"Crawl4AI: authenticated API users can run JavaScript in crawled pages","impact":"medium","summary":"Crawl4AI versions from 0.9.0 before 0.9.5 let an authenticated client of the Docker API server inject JavaScript through the css_selector and wait_for fields. The injected script runs in the crawled page, so an attacker can alter page state and the content the crawl returns.","audience":"developers","category":"ai-tooling","nicknames":[],"who_cares":["crawl4ai","docker","python"],"confidence":0.6,"fix_status":"available","needs_auth":"yes","worst_case":"Attacker runs JavaScript in crawled pages and alters returned content","analyst_note":"Confirm the Docker API server is the affected component and check the NVD entry for the fixed release notes; sources give only the NVD description.","how_to_check":"- Check the installed Crawl4AI version, for example with `pip show crawl4ai` or the image tag of the Docker deployment.\n- Confirm whether the Docker API server is reachable by clients outside your trusted group.","plain_action":"","needs_analyst":true,"not_affected_if":["library-only-use","api-server-not-deployed","version-0.9.5-or-later"],"who_is_affected":"Teams that run the Crawl4AI Docker API server with 0.9.0 up to but not including 0.9.5. Exposure requires an authenticated API client who can send css_selector or wait_for values; teams using Crawl4AI only as a library or not exposing the API server can likely skip it.","user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.00073,"input_tokens":4179,"output_tokens":625,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-119121':13A,16A '-2026':12A,15A '0.9.0':26B,71C '0.9.5':28B,73C 'ai':18B 'ai-tool':17B 'allow':85C 'allowlist':98C 'alter':60B,125C 'api':3A,36B,82C,87C 'arbitrari':91C 'attack':58B,105C 'authent':2A,31B,86C 'block':123C 'bypass':119C 'client':32B,88C 'code':122C 'condit':115C 'contain':74C 'content':65B,131C 'crawl':9A,54B,67B,95C,130C 'crawl4ai':1A,20B,23B,69C 'css':42B,99C,110C 'cve':11A,14A 'docker':21B,35B,81C 'field':47B,104C 'inject':38B,49B,77C,107C 'javascript':7A,39B,76C,92C 'js':114C,121C 'let':29B 'page':10A,55B,61B,96C,126C 'python':22B 'quot':108C 'return':68B,129C 'run':6A,51B,90C 'script':50B 'selector':43B,100C,111C 'server':37B,83C 'state':62B,127C 'suppli':113C 'tool':19B 'user':4A 'version':24B 'via':97C 'vulner':78C 'wait':45B,102C,117C","nicknames":[],"mitigations":[],"who_affected":"Teams that run the Crawl4AI Docker API server with 0.9.0 up to but not including 0.9.5. Exposure requires an authenticated API client who can send css_selector or wait_for values; teams using Crawl4AI only as a library or not exposing the API server can likely skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"developers","plain_action":null,"first_public_at":"2026-10-29T16:18:04+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/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":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-119121","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-119121","severity":null,"published_at":"2026-10-29T16:18:04+00:00","modified_at":"2026-10-29T16:18:04+00:00","first_seen_at":"2026-10-29T16:25:58+00:00","fetched_at":"2026-10-29T16:25:58+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"}