{"id":"CVE-2026-121721","kind":"vulnerability","aliases":["CVE-2026-121721"],"related":[],"title":"PublishPress Gutenberg Blocks: stored XSS through version 3.7.6","description":"Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in PublishPress Gutenberg Blocks advanced-gutenberg allows Stored XSS.This issue affects Gutenberg Blocks: from n/a through 3.7.6.","summary":"PublishPress Gutenberg Blocks (advanced-gutenberg) fails to neutralize input when generating web pages, allowing stored cross-site scripting. An attacker who can store content on the site can run scripts in other visitors' browsers.","severity":"medium","cvss":6.5,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"advanced-gutenberg","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["gutenberg-blocks","package","publishpress","wordpress"],"not_affected_if":["plugin-not-installed"],"how_to_check":"- Check the installed version of the Gutenberg Blocks (advanced-gutenberg) WordPress plugin in the plugin list or `wp plugin get advanced-gutenberg --field=version`","fix":"- Gutenberg Blocks (advanced-gutenberg): versions after `3.7.6` according to the affected range; the exact fixed version is unknown","status":"open","published_at":"2026-11-13T13:17:55+00:00","first_seen_at":"2026-11-13T13:46:51+00:00","triaged_at":"2026-11-13T13:48:01+00:00","updated_at":"2026-11-13T13:48:01+00:00","category":"package","confidence":0.6,"triage":{"at":"2026-11-13T13:48:01Z","model":"claude-haiku-5-5","output":{"fix":"- Gutenberg Blocks (advanced-gutenberg): versions after `3.7.6` according to the affected range; the exact fixed version is unknown","reach":"internet","title":"PublishPress Gutenberg Blocks: stored XSS through version 3.7.6","impact":"medium","summary":"PublishPress Gutenberg Blocks (advanced-gutenberg) fails to neutralize input when generating web pages, allowing stored cross-site scripting. An attacker who can store content on the site can run scripts in other visitors' browsers.","audience":"businesses","category":"package","nicknames":[],"who_cares":["wordpress","publishpress","gutenberg-blocks"],"confidence":0.6,"fix_status":"unknown","needs_auth":"unknown","worst_case":"Scripts run in other users' browsers on the site","analyst_note":"Confirm the fixed version and the required privilege level from the NVD entry or the PublishPress advisory.","how_to_check":"- Check the installed version of the Gutenberg Blocks (advanced-gutenberg) WordPress plugin in the plugin list or `wp plugin get advanced-gutenberg --field=version`\n- unknown","plain_action":"","product_name":"advanced-gutenberg","needs_analyst":true,"not_affected_if":["plugin-not-installed"],"who_is_affected":"unknown. The sources state the affected range is through 3.7.6 of the Gutenberg Blocks plugin for WordPress; stored XSS usually requires a user able to store content, but the sources do not say what role is needed.","user_interaction":"unknown","product_ecosystem":"vendor","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000753,"input_tokens":4557,"output_tokens":594,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-121721':11A,14A '-2026':10A,13A '3.7.6':8A,90C 'advanc':28B,78C 'advanced':16A 'advanced-gutenberg':15A,27B,77C 'affect':84C 'allow':38B,80C 'attack':45B 'block':3A,20B,26B,76C,86C 'browser':59B 'content':49B 'cross':41B,69C 'cross-sit':40B,68C 'cve':9A,12A 'fail':30B 'generat':35B,67C 'gutenberg':2A,17A,19B,25B,29B,75C,79C,85C 'gutenberg-block':18B 'improp':60C 'input':33B,63C 'issu':83C 'n/a':88C 'neutral':32B,61C 'packag':21B 'page':37B,66C 'publishpress':1A,22B,24B,74C 'run':54B 'script':43B,55B,71C 'site':42B,52B,70C 'store':4A,39B,48B,81C 'version':7A 'visitor':58B 'vulner':72C 'web':36B,65C 'wordpress':23B 'xss':5A 'xss.this':82C","nicknames":[],"mitigations":[],"who_affected":null,"tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"unknown","audience":"businesses","plain_action":null,"pkeys":["advancedgutenberg"],"ptokens":["advanced","gutenberg"],"labels":["gutenbergblocks","medium","package","publishpress","vendor","wordpress"],"campaign_type":null,"search_a":"'-121721':11A,14A '-2026':10A,13A '3.7.6':8A 'advanced':16A 'advanced-gutenberg':15A 'block':3A 'cve':9A,12A 'gutenberg':2A,17A 'publishpress':1A 'store':4A 'version':7A 'xss':5A","search_b":"'advanc':28B 'advanced-gutenberg':27B 'allow':38B 'attack':45B 'block':20B,26B 'browser':59B 'content':49B 'cross':41B 'cross-sit':40B 'fail':30B 'generat':35B 'gutenberg':19B,25B,29B 'gutenberg-block':18B 'input':33B 'neutral':32B 'packag':21B 'page':37B 'publishpress':22B,24B 'run':54B 'script':43B,55B 'site':42B,52B 'store':39B,48B 'visitor':58B 'web':36B 'wordpress':23B","search_c":"'3.7.6':90C 'advanc':78C 'advanced-gutenberg':77C 'affect':84C 'allow':80C 'block':76C,86C 'cross':69C 'cross-sit':68C 'generat':67C 'gutenberg':75C,79C,85C 'improp':60C 'input':63C 'issu':83C 'n/a':88C 'neutral':61C 'page':66C 'publishpress':74C 'script':71C 'site':70C 'store':81C 'vulner':72C 'web':65C 'xss.this':82C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-13T13:17:55+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L","cvss_by":"audit@patchstack.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121721","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121721","severity":null,"published_at":"2026-11-13T13:17:55+00:00","modified_at":"2026-11-13T13:17:55+00:00","first_seen_at":"2026-11-13T13:46:51+00:00","fetched_at":"2026-11-13T13:46:51+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}