{"id":"CVE-2026-121131","kind":"vulnerability","aliases":["CVE-2026-121131"],"related":[],"title":"Chrome for Android: use-after-free lets a crafted extension run code","description":"Use after free in Mobile in Google Chrome prior to 157.0.8103.38 allowed a remote attacker leveraging social engineering to execute arbitrary code outside the sandbox via a crafted Chrome extension. (Chromium security severity: High)","summary":"A use-after-free bug in the mobile build of Google Chrome lets an attacker who tricks a user into installing a crafted Chrome extension run arbitrary code outside the browser sandbox. Chromium rates it High severity.","severity":"high","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["android","browser-extensions","chrome","mobile","package"],"not_affected_if":["chrome-up-to-date","no-untrusted-extensions"],"how_to_check":"- Check the Chrome version on the device: open chrome://version and compare against `157.0.8103.38`\n- Review installed extensions on managed devices for unfamiliar or sideloaded ones","fix":"- Chrome Mobile: move to `157.0.8103.38` or later","status":"open","published_at":"2026-11-03T21:17:21+00:00","first_seen_at":"2026-11-03T21:19:21+00:00","triaged_at":"2026-11-03T21:24:48+00:00","updated_at":"2026-11-03T21:24:48+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-03T21:24:48Z","model":"claude-haiku-5-5","output":{"fix":"- Chrome Mobile: move to `157.0.8103.38` or later","reach":"internet","title":"Chrome for Android: use-after-free lets a crafted extension run code","impact":"high","summary":"A use-after-free bug in the mobile build of Google Chrome lets an attacker who tricks a user into installing a crafted Chrome extension run arbitrary code outside the browser sandbox. Chromium rates it High severity.","audience":"everyone","category":"package","nicknames":[],"who_cares":["chrome","android","mobile","browser-extensions"],"confidence":0.6,"fix_status":"available","needs_auth":"no","worst_case":"Attacker runs arbitrary code outside the browser sandbox on the device.","analyst_note":"Confirm the affected platforms (Android vs iOS vs desktop) and the fixed version for each from the Chrome stable release notes; the NVD entry does not name the platform beyond 'Mobile'.","how_to_check":"- Check the Chrome version on the device: open chrome://version and compare against `157.0.8103.38`\n- Review installed extensions on managed devices for unfamiliar or sideloaded ones","plain_action":"Update Google Chrome on your Android phone or tablet to version 157.0.8103.38 or later, and only add extensions you trust.","needs_analyst":true,"not_affected_if":["chrome-up-to-date","no-untrusted-extensions"],"who_is_affected":"Any device running Chrome Mobile before 157.0.8103.38 is exposed, but exploitation needs the user to be socially engineered into installing a crafted extension. Desktop Chrome and managed fleets should be checked against their own version ranges, which the sources do not cover. Devices already on 157.0.8103.38 or later are not affected.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000734,"input_tokens":4109,"output_tokens":646,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121131':16A,19A '-2026':15A,18A '157.0.8103.38':75C 'allow':76C 'android':3A,20B 'arbitrari':54B,85C 'attack':42B,79C 'browser':22B,58B 'browser-extens':21B 'bug':32B 'build':36B 'chrome':1A,24B,39B,51B,72C,93C 'chromium':60B,95C 'code':13A,55B,86C 'craft':10A,50B,92C 'cve':14A,17A 'engin':82C 'execut':84C 'extens':11A,23B,52B,94C 'free':7A,31B,67C 'googl':38B,71C 'high':63B,98C 'instal':48B 'let':8A,40B 'leverag':80C 'mobil':25B,35B,69C 'outsid':56B,87C 'packag':26B 'prior':73C 'rate':61B 'remot':78C 'run':12A,53B 'sandbox':59B,89C 'secur':96C 'sever':64B,97C 'social':81C 'trick':44B 'use':5A,29B,65C 'use-after-fre':4A,28B 'user':46B 'via':90C","nicknames":[],"mitigations":[],"who_affected":"Any device running Chrome Mobile before 157.0.8103.38 is exposed, but exploitation needs the user to be socially engineered into installing a crafted extension. Desktop Chrome and managed fleets should be checked against their own version ranges, which the sources do not cover. Devices already on 157.0.8103.38 or later are not affected.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"everyone","plain_action":"Update Google Chrome on your Android phone or tablet to version 157.0.8103.38 or later, and only add extensions you trust.","pkeys":[],"ptokens":[],"labels":["android","browserextensions","chrome","high","mobile","package"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:21+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121131","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121131","severity":null,"published_at":"2026-11-03T21:17:21+00:00","modified_at":"2026-11-03T21:17:21+00:00","first_seen_at":"2026-11-03T21:19:21+00:00","fetched_at":"2026-11-03T21:19:21+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"}