{"id":"CVE-2026-112784","kind":"vulnerability","aliases":["CVE-2026-112784"],"related":[],"title":"OpenCATS: any logged-in user can send mail via SMTP relay","description":"OpenCATS before 0.10.0 contains a missing authorization vulnerability in ajax/testEmailSettings.php that allows any authenticated user to send mail through the configured SMTP relay. Read-level users can supply testEmailAddress and fromAddress parameters to send the fixed test message to any recipient with a spoofed From address.","summary":"OpenCATS before 0.10.0 lacks an authorization check on ajax/testEmailSettings.php, so any authenticated user, including read-only accounts, can trigger a test email. The attacker chooses the recipient and From address, enabling spoofed mail sent through the configured SMTP relay.","severity":"medium","cvss":5.3,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["opencats","package","php","self-hosted","smtp"],"not_affected_if":["version-0.10.0-or-later"],"how_to_check":"- Look for `ajax/testEmailSettings.php` in the OpenCATS install directory\n- Check the installed version against `0.10.0`; anything below is affected\n- unknown whether the sources give a version-specific string check beyond this","fix":"- Upgrade OpenCATS to `0.10.0` or later\n- Until upgraded, restrict or disable access to `ajax/testEmailSettings.php` at the web server level\n- Rotate the SMTP relay credentials if abuse is suspected","status":"open","published_at":"2026-10-20T11:17:18+00:00","first_seen_at":"2026-10-23T21:57:20+00:00","triaged_at":"2026-10-25T04:24:51+00:00","updated_at":"2026-10-25T04:24:51+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T04:24:51Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade OpenCATS to `0.10.0` or later\n- Until upgraded, restrict or disable access to `ajax/testEmailSettings.php` at the web server level\n- Rotate the SMTP relay credentials if abuse is suspected","reach":"internet","title":"OpenCATS: any logged-in user can send mail via SMTP relay","impact":"medium","summary":"OpenCATS before 0.10.0 lacks an authorization check on ajax/testEmailSettings.php, so any authenticated user, including read-only accounts, can trigger a test email. The attacker chooses the recipient and From address, enabling spoofed mail sent through the configured SMTP relay.","category":"package","nicknames":[],"who_cares":["opencats","self-hosted","smtp","php"],"confidence":0.7,"needs_auth":"yes","worst_case":"Attacker sends spoofed mail to anyone through the company SMTP relay","analyst_note":"Confirm the exact fixed commit and whether the SMTP relay default config is exposed; check nvd detail page for the affected version range.","how_to_check":"- Look for `ajax/testEmailSettings.php` in the OpenCATS install directory\n- Check the installed version against `0.10.0`; anything below is affected\n- unknown whether the sources give a version-specific string check beyond this","needs_analyst":true,"not_affected_if":["version-0.10.0-or-later"],"who_is_affected":"Teams that self-host OpenCATS before 0.10.0 with an SMTP relay configured. Any user with an account, including read-level users, can reach the flawed endpoint, so the risk is about who holds accounts. Instances without a configured relay or on 0.10.0 or later are not affected.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000651,"input_tokens":3337,"output_tokens":634,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-112784':15A,18A '-2026':14A,17A '0.10.0':28B,68C 'account':43B 'address':56B,112C 'ajax/testemailsettings.php':34B,75C 'allow':77C 'attack':50B 'authent':37B,79C 'author':31B,72C 'check':32B 'choos':51B 'configur':63B,86C 'contain':69C 'cve':13A,16A 'email':48B 'enabl':57B 'fix':102C 'fromaddress':97C 'host':24B 'includ':39B 'lack':29B 'level':91C 'log':4A 'logged-in':3A 'mail':9A,59B,83C 'messag':104C 'miss':71C 'opencat':1A,19B,26B,66C 'packag':20B 'paramet':98C 'php':21B 'read':41B,90C 'read-level':89C 'read-on':40B 'recipi':53B,107C 'relay':12A,65B,88C 'self':23B 'self-host':22B 'send':8A,82C,100C 'sent':60B 'smtp':11A,25B,64B,87C 'spoof':58B,110C 'suppli':94C 'test':47B,103C 'testemailaddress':95C 'trigger':45B 'user':6A,38B,80C,92C 'via':10A 'vulner':73C","nicknames":[],"mitigations":[],"who_affected":"Teams that self-host OpenCATS before 0.10.0 with an SMTP relay configured. Any user with an account, including read-level users, can reach the flawed endpoint, so the risk is about who holds accounts. Instances without a configured relay or on 0.10.0 or later are not affected.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T11:17:18+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-2026-112784","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-112784","severity":null,"published_at":"2026-10-20T11:17:18+00:00","modified_at":"2026-10-20T14:16:57+00:00","first_seen_at":"2026-10-23T21:57:20+00:00","fetched_at":"2026-10-23T22:28:58+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"}