{"id":"CVE-2026-121211","kind":"vulnerability","aliases":["CVE-2026-121211"],"related":[],"title":"Chrome: use-after-free in PowerBookmarks lets a crafted extension run code","description":"Use after free in PowerBookmarks in Google Chrome prior to 157.0.8103.38 allowed a remote attacker who had compromised the renderer process and leveraged 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 PowerBookmarks feature of Google Chrome can be chained by an attacker who already controls the renderer process and uses social engineering to get a crafted Chrome extension installed. The result is arbitrary code execution outside the browser sandbox.","severity":"high","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","desktop","runtime"],"not_affected_if":["chrome-updated","extensions-locked-down"],"how_to_check":"- Check the Chrome version with `chrome://version` or the About page\n- Review installed extensions at `chrome://extensions` for anything unexpected","fix":"- Google Chrome: move to `157.0.8103.38` or later","status":"open","published_at":"2026-11-03T21:17:30+00:00","first_seen_at":"2026-11-03T21:19:26+00:00","triaged_at":"2026-11-03T21:22:40+00:00","updated_at":"2026-11-03T21:22:40+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-11-03T21:22:40Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later","reach":"internet","title":"Chrome: use-after-free in PowerBookmarks lets a crafted extension run code","impact":"high","summary":"A use-after-free bug in the PowerBookmarks feature of Google Chrome can be chained by an attacker who already controls the renderer process and uses social engineering to get a crafted Chrome extension installed. The result is arbitrary code execution outside the browser sandbox.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","desktop"],"confidence":0.7,"fix_status":"available","needs_auth":"no","worst_case":"Arbitrary code runs outside the browser sandbox on the user's machine","analyst_note":"","how_to_check":"- Check the Chrome version with `chrome://version` or the About page\n- Review installed extensions at `chrome://extensions` for anything unexpected","plain_action":"Update Google Chrome to version 157.0.8103.38 or later.","needs_analyst":false,"not_affected_if":["chrome-updated","extensions-locked-down"],"who_is_affected":"Desktop Chrome users running a version earlier than 157.0.8103.38. The attack first needs a compromised renderer and a user who installs a malicious extension, so exposure depends on extension installs. Organizations that manage Chrome fleets should confirm the managed version.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000677,"input_tokens":4125,"output_tokens":529,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121211':16A,19A '-2026':15A,18A '157.0.8103.38':80C 'allow':81C 'alreadi':44B 'arbitrari':63B,97C 'attack':42B,84C 'browser':20B,68B 'bug':29B 'chain':39B 'chrome':1A,21B,36B,57B,77C,105C 'chromium':107C 'code':13A,64B,98C 'compromis':87C 'control':45B 'craft':10A,56B,104C 'cve':14A,17A 'desktop':22B 'engin':52B,94C 'execut':65B,96C 'extens':11A,58B,106C 'featur':33B 'free':5A,28B,72C 'get':54B 'googl':35B,76C 'high':110C 'instal':59B 'let':8A 'leverag':92C 'outsid':66B,99C 'powerbookmark':7A,32B,74C 'prior':78C 'process':48B,90C 'remot':83C 'render':47B,89C 'result':61B 'run':12A 'runtim':23B 'sandbox':69B,101C 'secur':108C 'sever':109C 'social':51B,93C 'use':3A,26B,50B,70C 'use-after-fre':2A,25B 'via':102C","nicknames":[],"mitigations":[],"who_affected":"Desktop Chrome users running a version earlier than 157.0.8103.38. The attack first needs a compromised renderer and a user who installs a malicious extension, so exposure depends on extension installs. Organizations that manage Chrome fleets should confirm the managed version.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"everyone","plain_action":"Update Google Chrome to version 157.0.8103.38 or later.","pkeys":[],"ptokens":[],"labels":["browsers","chrome","desktop","high","runtime"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:30+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121211","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121211","severity":null,"published_at":"2026-11-03T21:17:30+00:00","modified_at":"2026-11-03T21:17:30+00:00","first_seen_at":"2026-11-03T21:19:26+00:00","fetched_at":"2026-11-03T21:19:26+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"}