{"id":"CVE-2026-114725","kind":"vulnerability","aliases":["CVE-2026-114725"],"related":[],"title":"Roundcube Webmail: header injection lets logged-in users add mail headers","description":"Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability. rcmail_sendmail stripped newline characters only from the Subject and Organization headers, leaving other header values taken from request parameters unsanitized, so a remote authenticated attacker could inject arbitrary headers into an outgoing message via the References, In-Reply-To, Message-ID and From parameters. Upstream fixed this in the commit “Fix mail header injection via References/In-Reply-To/Message-ID/From parameters”, which normalizes whitespace in every string header value.","summary":"Roundcube Webmail does not strip newlines from the References, In-Reply-To, Message-ID and From fields when sending mail, so a logged-in user can inject extra headers into outgoing messages. The attacker gets to shape the headers of mail sent through the server, which can be used to spoof or manipulate messages.","severity":"medium","cvss":5.0,"epss":0.00286,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["mail-server","package","roundcube","self-hosted","webmail"],"not_affected_if":["already-patched","no-user-accounts"],"how_to_check":"- Check the installed version with `grep -i \"RCMAIL_VERSION\" program/include/iniset.php` in the Roundcube install directory\n- Compare against the fixed releases: any `1.6.x` below `1.6.20` or any `1.7.x` below `1.7.5` is exposed","fix":"- Upgrade Roundcube Webmail to `1.6.20` on the 1.6 branch or `1.7.5` on the 1.7 branch\n- Apply the upstream commit \"Fix mail header injection via References/In-Reply-To/Message-ID/From parameters\" if you cannot upgrade yet","status":"open","published_at":"2026-10-22T02:17:00+00:00","first_seen_at":"2026-10-23T21:57:30+00:00","triaged_at":"2026-10-25T04:29:25+00:00","updated_at":"2026-10-25T04:29:25+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T04:29:25Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Roundcube Webmail to `1.6.20` on the 1.6 branch or `1.7.5` on the 1.7 branch\n- Apply the upstream commit \"Fix mail header injection via References/In-Reply-To/Message-ID/From parameters\" if you cannot upgrade yet","reach":"internet","title":"Roundcube Webmail: header injection lets logged-in users add mail headers","impact":"medium","summary":"Roundcube Webmail does not strip newlines from the References, In-Reply-To, Message-ID and From fields when sending mail, so a logged-in user can inject extra headers into outgoing messages. The attacker gets to shape the headers of mail sent through the server, which can be used to spoof or manipulate messages.","category":"package","nicknames":[],"who_cares":["roundcube","self-hosted","webmail","mail-server"],"confidence":0.7,"needs_auth":"yes","worst_case":"Authenticated users inject arbitrary headers into outgoing mail","analyst_note":"","how_to_check":"- Check the installed version with `grep -i \"RCMAIL_VERSION\" program/include/iniset.php` in the Roundcube install directory\n- Compare against the fixed releases: any `1.6.x` below `1.6.20` or any `1.7.x` below `1.7.5` is exposed","needs_analyst":false,"not_affected_if":["already-patched","no-user-accounts"],"who_is_affected":"Any Roundcube Webmail installation on the affected 1.6 or 1.7 branches is exposed, since the flaw sits in the shared send path used by every user. The attacker needs a valid mail account on that Roundcube instance, so public-facing installs with open or self-registration are the most at risk. Installs that are already on the fixed versions can skip it.","user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000676,"input_tokens":3473,"output_tokens":657,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-114725':15A,18A '-2026':14A,17A '1.6.20':88C '1.7':90C '1.7.5':93C 'add':10A 'affect':95C 'arbitrari':130C 'attack':64B,127C 'authent':126C 'charact':106C 'commit':154C 'could':128C 'cve':13A,16A 'everi':166C 'extra':58B 'field':46B 'fix':150C,155C 'get':65B 'header':3A,12A,59B,69B,99C,113C,116C,131C,157C,168C 'host':26B 'id':43B,145C 'in-reply-to':37B,139C 'inject':4A,57B,100C,129C,158C 'leav':114C 'let':5A 'log':7A,53B 'logged-in':6A,52B 'mail':11A,20B,49B,71B,98C,156C 'mail-serv':19B 'manipul':83B 'messag':42B,62B,84B,135C,144C 'message-id':41B,143C 'newlin':33B,105C 'normal':163C 'organ':112C 'outgo':61B,134C 'packag':22B 'paramet':121C,148C,161C 'rcmail':102C 'refer':36B,138C 'references/in-reply-to/message-id/from':160C 'remot':125C 'repli':39B,141C 'request':120C 'roundcub':1A,23B,28B,85C 'self':25B 'self-host':24B 'send':48B 'sendmail':103C 'sent':72B 'server':21B,75B 'shape':67B 'spoof':81B 'string':167C 'strip':32B,104C 'subject':110C 'taken':118C 'unsanit':122C 'upstream':149C 'use':79B 'user':9A,55B 'valu':117C,169C 'via':136C,159C 'vulner':101C 'webmail':2A,27B,29B,86C 'whitespac':164C 'x':91C","nicknames":[],"mitigations":[],"who_affected":"Any Roundcube Webmail installation on the affected 1.6 or 1.7 branches is exposed, since the flaw sits in the shared send path used by every user. The attacker needs a valid mail account on that Roundcube instance, so public-facing installs with open or self-registration are the most at risk. Installs that are already on the fixed versions can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-22T02:17:00+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N","cvss_by":"cve@mitre.org","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-114725","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-114725","severity":null,"published_at":"2026-10-22T02:17:00+00:00","modified_at":"2026-10-22T16:45:49+00:00","first_seen_at":"2026-10-23T21:57:30+00:00","fetched_at":"2026-10-23T22:29:02+00:00","note":null},{"source":"epss","external_id":"CVE-2026-114725","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-114725","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-24T07:15:52+00:00","fetched_at":"2026-10-24T07:15:52+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"}