{"id":"CVE-2026-120477","kind":"vulnerability","aliases":["CVE-2026-120477"],"related":[],"title":"Stop Spammers Classic WordPress plugin: stored XSS via author field","description":"The Stop Spammers Classic plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'author' POST parameter in versions up to, and including, 2026.6. An unauthenticated POST handled on init stores the attacker-supplied author field (after sanitize_text_field, which does not escape single quotes) into the ss_stop_sp_reg_stats option history. The Log Report admin page then renders that stored value inside a single-quoted JavaScript string within a double-quoted onclick attribute using esc_js(); because esc_js() uses _wp_specialchars with ENT_COMPAT it does not escape single quotes, allowing the stored value to break out of the JS string literal and inject arbitrary JavaScript. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute whenever an administrator with manage_options access clicks the 'Report to SFS' link on an attacker-poisoned log row (the StopForumSpam API key must be configured for that link to be rendered — the field is empty by default). Successful exploitation additionally requires an action by an administrator — the attacker cannot trigger the vulnerability on their own.","summary":"The Stop Spammers Classic WordPress plugin up to version 2026.6 stores an unauthenticated 'author' value in its log and later renders it unsafely in the admin Log Report page. An attacker can inject JavaScript that runs in an administrator's browser when they click the 'Report to SFS' link on a poisoned log row.","severity":"medium","cvss":4.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["package","self-hosted","wordpress","wordpress-plugin"],"not_affected_if":["api-key-not-configured","plugin-newer-than-2026.6","plugin-not-installed"],"how_to_check":"- Check the installed Stop Spammers Classic plugin version in the WordPress admin Plugins screen; versions `2026.6` and earlier are affected.\n- Check whether the StopForumSpam API key is set in the plugin settings; the 'Report to SFS' link only renders when it is configured.","fix":null,"status":"open","published_at":"2026-11-07T05:18:11+00:00","first_seen_at":"2026-11-07T05:45:57+00:00","triaged_at":"2026-11-07T05:54:23+00:00","updated_at":"2026-11-07T05:54:23+00:00","category":"package","confidence":0.8,"triage":{"at":"2026-11-07T05:54:23Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"internet","title":"Stop Spammers Classic WordPress plugin: stored XSS via author field","impact":"medium","summary":"The Stop Spammers Classic WordPress plugin up to version 2026.6 stores an unauthenticated 'author' value in its log and later renders it unsafely in the admin Log Report page. An attacker can inject JavaScript that runs in an administrator's browser when they click the 'Report to SFS' link on a poisoned log row.","audience":"businesses","category":"package","nicknames":[],"who_cares":["wordpress","wordpress-plugin","self-hosted"],"confidence":0.8,"fix_status":"unknown","needs_auth":"no","worst_case":"Injected script runs in an administrator's browser session","analyst_note":"","how_to_check":"- Check the installed Stop Spammers Classic plugin version in the WordPress admin Plugins screen; versions `2026.6` and earlier are affected.\n- Check whether the StopForumSpam API key is set in the plugin settings; the 'Report to SFS' link only renders when it is configured.","plain_action":"","needs_analyst":false,"not_affected_if":["plugin-not-installed","api-key-not-configured","plugin-newer-than-2026.6"],"who_is_affected":"Sites running the Stop Spammers Classic plugin up to and including 2026.6 where the StopForumSpam API key is configured, so the 'Report to SFS' link appears on the Log Report page. Exploitation needs an administrator with manage_options to click that link, so sites without the API key configured or without the plugin are not exposed.","user_interaction":"yes","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000749,"input_tokens":4527,"output_tokens":593,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-120477':13A,16A '-2026':12A,15A '2026.6':34B,105C 'access':218C 'action':256C 'addit':253C 'admin':50B,141C 'administr':63B,214C,259C 'allow':180C 'api':234C 'arbitrari':194C,205C 'attack':55B,115C,202C,228C,261C 'attacker-poison':227C 'attacker-suppli':114C 'attribut':161C 'author':9A,38B,96C,117C 'break':185C 'browser':65B 'cannot':262C 'classic':3A,28B,82C 'click':68B,219C 'compat':173C 'configur':238C 'cross':91C 'cross-sit':90C 'cve':11A,14A 'default':250C 'doubl':158C 'double-quot':157C 'empti':248C 'ent':172C 'esc':163C,166C 'escap':126C,177C 'execut':211C 'exploit':252C 'field':10A,118C,122C,246C 'handl':109C 'histori':137C 'host':20B 'includ':104C 'init':111C 'inject':57B,193C,204C 'insid':148C 'javascript':58B,153C,195C 'js':164C,167C,189C 'key':235C 'later':44B 'link':73B,224C,241C 'liter':191C 'log':42B,51B,77B,139C,230C 'make':197C 'manag':216C 'must':236C 'onclick':160C 'option':136C,217C 'packag':17B 'page':53B,142C,209C 'paramet':98C 'plugin':5A,24B,30B,83C 'poison':76B,229C 'possibl':199C 'post':97C,108C 'quot':128C,152C,159C,179C 'reg':134C 'render':45B,144C,244C 'report':52B,70B,140C,221C 'requir':254C 'row':78B,231C 'run':60B 'sanit':120C 'script':93C,207C 'self':19B 'self-host':18B 'sfs':72B,223C 'singl':127C,151C,178C 'single-quot':150C 'site':92C 'sp':133C 'spammer':2A,27B,81C 'specialchar':170C 'ss':131C 'stat':135C 'stop':1A,26B,80C,132C 'stopforumspam':233C 'store':6A,35B,89C,112C,146C,182C 'string':154C,190C 'success':251C 'suppli':116C 'text':121C 'trigger':263C 'unauthent':37B,107C,201C 'unsaf':47B 'use':162C,168C 'valu':39B,147C,183C 'version':33B,100C 'via':8A,94C 'vulner':87C,265C 'web':206C 'whenev':212C 'within':155C 'wordpress':4A,21B,23B,29B,85C 'wordpress-plugin':22B 'wp':169C 'xss':7A","nicknames":[],"mitigations":[],"who_affected":"Sites running the Stop Spammers Classic plugin up to and including 2026.6 where the StopForumSpam API key is configured, so the 'Report to SFS' link appears on the Log Report page. Exploitation needs an administrator with manage_options to click that link, so sites without the API key configured or without the plugin are not exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["medium","package","selfhosted","wordpress","wordpressplugin"],"campaign_type":null,"search_a":"'-120477':13A,16A '-2026':12A,15A 'author':9A 'classic':3A 'cve':11A,14A 'field':10A 'plugin':5A 'spammer':2A 'stop':1A 'store':6A 'via':8A 'wordpress':4A 'xss':7A","search_b":"'2026.6':34B 'admin':50B 'administr':63B 'attack':55B 'author':38B 'browser':65B 'classic':28B 'click':68B 'host':20B 'inject':57B 'javascript':58B 'later':44B 'link':73B 'log':42B,51B,77B 'packag':17B 'page':53B 'plugin':24B,30B 'poison':76B 'render':45B 'report':52B,70B 'row':78B 'run':60B 'self':19B 'self-host':18B 'sfs':72B 'spammer':27B 'stop':26B 'store':35B 'unauthent':37B 'unsaf':47B 'valu':39B 'version':33B 'wordpress':21B,23B,29B 'wordpress-plugin':22B","search_c":"'2026.6':105C 'access':218C 'action':256C 'addit':253C 'admin':141C 'administr':214C,259C 'allow':180C 'api':234C 'arbitrari':194C,205C 'attack':115C,202C,228C,261C 'attacker-poison':227C 'attacker-suppli':114C 'attribut':161C 'author':96C,117C 'break':185C 'cannot':262C 'classic':82C 'click':219C 'compat':173C 'configur':238C 'cross':91C 'cross-sit':90C 'default':250C 'doubl':158C 'double-quot':157C 'empti':248C 'ent':172C 'esc':163C,166C 'escap':126C,177C 'execut':211C 'exploit':252C 'field':118C,122C,246C 'handl':109C 'histori':137C 'includ':104C 'init':111C 'inject':193C,204C 'insid':148C 'javascript':153C,195C 'js':164C,167C,189C 'key':235C 'link':224C,241C 'liter':191C 'log':139C,230C 'make':197C 'manag':216C 'must':236C 'onclick':160C 'option':136C,217C 'page':142C,209C 'paramet':98C 'plugin':83C 'poison':229C 'possibl':199C 'post':97C,108C 'quot':128C,152C,159C,179C 'reg':134C 'render':144C,244C 'report':140C,221C 'requir':254C 'row':231C 'sanit':120C 'script':93C,207C 'sfs':223C 'singl':127C,151C,178C 'single-quot':150C 'site':92C 'sp':133C 'spammer':81C 'specialchar':170C 'ss':131C 'stat':135C 'stop':80C,132C 'stopforumspam':233C 'store':89C,112C,146C,182C 'string':154C,190C 'success':251C 'suppli':116C 'text':121C 'trigger':263C 'unauthent':107C,201C 'use':162C,168C 'valu':147C,183C 'version':100C 'via':94C 'vulner':87C,265C 'web':206C 'whenev':212C 'within':155C 'wordpress':85C 'wp':169C","first_public_at":"2026-11-07T05:18:11+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N","cvss_by":"security@wordfence.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-120477","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120477","severity":null,"published_at":"2026-11-07T05:18:11+00:00","modified_at":"2026-11-07T05:18:11+00:00","first_seen_at":"2026-11-07T05:45:57+00:00","fetched_at":"2026-11-07T05:45:57+00:00","note":null}],"documents":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}