{"id":"CVE-2026-114717","kind":"vulnerability","aliases":["CVE-2026-114717"],"related":[],"title":"Roundcube Webmail: forwarded-as-attachment subject lets mail headers be injected","description":"Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability when a message is forwarded as an attachment. The subject of the forwarded message was used verbatim to generate the attachment name, so a received message whose subject contains CRLF sequences could inject arbitrary MIME part headers into the outgoing message. Upstream fixed this in the commit “Fix mail header injection via subject of a message forwarded as attachment”, which collapses whitespace in the generated name.","summary":"Roundcube builds the attachment name for a forwarded message directly from that message's subject, without stripping line breaks. A received email whose subject contains CRLF sequences can therefore inject extra MIME part headers into the outgoing message.","severity":"medium","cvss":4.0,"epss":0.00298,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["mail","package","roundcube","self-hosted"],"not_affected_if":["patched-version"],"how_to_check":"- Check the Roundcube version: `1.6.x` below `1.6.20` or `1.7.x` below `1.7.5` is affected.\n- Confirm the installed release from the Roundcube package or the `program/include/iniset.php` version constant.","fix":"- Upgrade Roundcube to `1.6.20` or later on the 1.6 line, or to `1.7.5` or later on the 1.7 line.\n- Until patched, unknown whether a configuration change mitigates it; the sources do not say.","status":"open","published_at":"2026-10-22T02:16:59+00:00","first_seen_at":"2026-10-23T21:57:30+00:00","triaged_at":"2026-10-25T04:41:51+00:00","updated_at":"2026-10-25T04:41:51+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T04:41:51Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Roundcube to `1.6.20` or later on the 1.6 line, or to `1.7.5` or later on the 1.7 line.\n- Until patched, unknown whether a configuration change mitigates it; the sources do not say.","reach":"internet","title":"Roundcube Webmail: forwarded-as-attachment subject lets mail headers be injected","impact":"low","summary":"Roundcube builds the attachment name for a forwarded message directly from that message's subject, without stripping line breaks. A received email whose subject contains CRLF sequences can therefore inject extra MIME part headers into the outgoing message.","category":"package","nicknames":[],"who_cares":["roundcube","self-hosted","mail"],"confidence":0.7,"needs_auth":"no","worst_case":"Attacker injects extra MIME headers into outgoing forwarded mail","analyst_note":"","how_to_check":"- Check the Roundcube version: `1.6.x` below `1.6.20` or `1.7.x` below `1.7.5` is affected.\n- Confirm the installed release from the Roundcube package or the `program/include/iniset.php` version constant.","needs_analyst":false,"not_affected_if":["patched-version"],"who_is_affected":"Any self-hosted or managed Roundcube deployment on the affected versions where users forward messages as attachments. Injection affects outgoing mail composed by users who receive hostile subjects, so exposure depends on accepting mail from untrusted senders. Deployments already on 1.6.20 or 1.7.5 or later are not affected.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000633,"input_tokens":3446,"output_tokens":576,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-114717':15A,18A '-2026':14A,17A '1.6.20':66C '1.7':68C '1.7.5':71C 'affect':73C 'arbitrari':113C 'attach':6A,28B,87C,100C,138C 'break':43B 'build':26B 'collaps':140C 'commit':126C 'contain':49B,108C 'could':111C 'crlf':50B,109C 'cve':13A,16A 'direct':34B 'email':46B 'extra':55B 'fix':122C,127C 'forward':4A,32B,84C,92C,136C 'forwarded-as-attach':3A 'generat':98C,144C 'header':10A,58B,77C,116C,129C 'host':24B 'inject':12A,54B,78C,112C,130C 'let':8A 'line':42B 'mail':9A,19B,76C,128C 'messag':33B,37B,62B,82C,93C,105C,120C,135C 'mime':56B,114C 'name':29B,101C,145C 'outgo':61B,119C 'packag':20B 'part':57B,115C 'receiv':45B,104C 'roundcub':1A,21B,25B,63C 'self':23B 'self-host':22B 'sequenc':51B,110C 'strip':41B 'subject':7A,39B,48B,89C,107C,132C 'therefor':53B 'upstream':121C 'use':95C 'verbatim':96C 'via':131C 'vulner':79C 'webmail':2A,64C 'whitespac':141C 'whose':47B,106C 'without':40B 'x':69C","nicknames":[],"mitigations":[],"who_affected":"Any self-hosted or managed Roundcube deployment on the affected versions where users forward messages as attachments. Injection affects outgoing mail composed by users who receive hostile subjects, so exposure depends on accepting mail from untrusted senders. Deployments already on 1.6.20 or 1.7.5 or later are not affected.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-22T02:16:59+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N","cvss_by":"cve@mitre.org","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-114717","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-114717","severity":null,"published_at":"2026-10-22T02:16:59+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-2026-114717","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-114717","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"}