{"id":"CVE-2026-121946","aliases":["EUVD-2026-116903","GHSA-5gqw-c8wj-82xp","GHSA-gmgm-r6fh-fq6g"],"status":"published","title":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 CRLF Header Injection via Message Builders","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00325,"percentile":0.25947,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-93"],"published":"2026-11-04T12:31:23Z","modified":"2026-11-05T03:31:18Z","products":[{"vendor":"zbateson","product":"mail-mime-parser"}],"references":[{"url":"https://github.com/zbateson/mail-mime-parser/security/advisories/GHSA-gmgm-r6fh-fq6g","tags":["vendor-advisory","exploit","advisory"]},{"url":"https://github.com/zbateson/mail-mime-parser/commit/f385b2923023a9a7b69003468e363a4661f1c85a","tags":["patch","fix"]},{"url":"https://github.com/zbateson/mail-mime-parser/commit/1fa840ef367958e991e6840b4e3ffd41aca9d147","tags":["patch","fix"]},{"url":"https://github.com/zbateson/mail-mime-parser/commit/c31c62ccc3e66a7a7da0d79954ef83807f9daa20","tags":["patch","fix"]},{"url":"https://github.com/zbateson/mail-mime-parser/commit/b032920875c6cb35bb2ddd7abfd7e98608d75bc0","tags":["patch","fix"]},{"url":"https://github.com/zbateson/mail-mime-parser/blob/4.0.5/src/Message/Helper/MultipartHelper.php#L270-L273","tags":["technical-description","article"]},{"url":"https://www.vulncheck.com/advisories/zbateson-mail-mime-parser-before-3.0.9-and-4-x-before-4.0.6-crlf-header-injection-via-message-builders","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121946","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-5gqw-c8wj-82xp"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/121xxx/CVE-2026-121946.json","tags":["advisory"]},{"url":"https://github.com/zbateson/mail-mime-parser","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-121946","title":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 CRLF Header Injection via Message Builders","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","status":"published","published":"2026-11-04T12:31:23.166Z","modified":"2026-11-04T18:49:31.556Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-93"],"updated_at":"2026-11-04T19:37:11.952963Z"}],"euvd":[{"id":"EUVD-2026-116903","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","status":"published","published":"2026-11-04T12:31:23Z","modified":"2026-11-04T18:49:31Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-04T20:13:45.839046Z"}],"ghsa":[{"id":"GHSA-5gqw-c8wj-82xp","title":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection...","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","status":"published","published":"2026-11-04T15:32:30Z","modified":"2026-11-04T15:32:31Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/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","level":"medium"},{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high"}],"cwes":["CWE-93"],"updated_at":"2026-11-04T15:52:09.418756Z"}],"nvd":[{"id":"CVE-2026-121946","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","status":"published","published":"2026-11-04T13:17:29.477Z","modified":"2026-11-12T21:36:06.743Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/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","level":"medium","assessor":"secondary"},{"version":"3.1","score":7.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-93"],"updated_at":"2026-11-12T23:33:06.861048Z"}],"osv":[{"id":"CVE-2026-121946","title":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 CRLF Header Injection via Message Builders","description":"zbateson mail-mime-parser before 3.0.9 and 4.x before 4.0.6 contains a CRLF header injection vulnerability in message-building helpers that fail to strip CR and LF characters. Attackers supplying crafted MIME type, charset, encoding, micalg, or protocol values can inject extra header lines such as a forged Bcc into outgoing messages.","status":"published","published":"2026-11-04T12:31:23.166Z","modified":"2026-11-05T21:32:22.305768357Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-93"],"updated_at":"2026-11-05T22:00:34.245765Z"}]}}