{"id":"CVE-2026-44240","aliases":["GHSA-rpmf-866q-6p89"],"url":"https://o3.security/vulnerability/CVE-2026-44240","summary":"basic-ftp allows a malicious FTP server to cause client-side denial of service via unbounded multiline control response buffering","details":"basic-ftp is an FTP client for Node.js. Prior to 5.3.1, basic-ftp is vulnerable to client-side denial of service when parsing FTP control-channel multiline responses. A malicious or compromised FTP server can send an unterminated multiline response during the initial FTP banner phase, before authentication. The client keeps appending attacker-controlled data into FtpContext._partialResponse and repeatedly reparses the accumulated buffer without enforcing a maximum control response size. As a result, an application using basic-ftp can remain stuck in connect() while memory and CPU usage grow under attacker-controlled input. This can lead to process-level denial of service, container OOM kills, worker restarts, queue backlog, or service degradation in applications that automatically connect to FTP endpoints. This vulnerability is fixed in 5.3.1.","published":"2026-05-12T20:37:43.098Z","modified":"2026-08-12T03:51:11.754261254Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00465,"percentile":0.38199,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"basic-ftp","fixedVersion":"5.3.1"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44240.json"},{"type":"ADVISORY","url":"https://github.com/patrickjuchli/basic-ftp/security/advisories/GHSA-rpmf-866q-6p89"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44240"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:11.754261254Z"}}