{"items":[{"id":"NVI-00017504","kind":"vulnerability","title":"aiosmtplib vulnerable to SMTP command injection via CR/LF in sender/recipient address","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-v3q9-hj7j-63hq","CVE-2026-53533"],"plain_summary":"GitHub lists this reviewed advisory for aiosmtplib. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-0cbdc01e016790fd31752fae36cf072a"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-0cbdc01e016790fd31752fae36cf072a","url":"https://github.com/advisories/GHSA-v3q9-hj7j-63hq","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-v3q9-hj7j-63hq","publisher":"GitHub Advisory Database","observed_at":"2026-11-04T23:34:51.634Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-0cbdc01e016790fd31752fae36cf072a"],"technology":"aiosmtplib","known_exclusions":[],"conditions_summary":"### Summary\n\n`aiosmtplib`'s `SMTP.mail()`, `SMTP.rcpt()`, `SMTP.vrfy()` and `SMTP.expn()` send the caller-supplied email address to the server without rejecting embedded CR/LF (`\\r\\n`) bytes. An address that contains a CR/LF is written verbatim onto the SMTP control connection, so the bytes after the CRLF are framed by the server as one or more **additional, standalone SMTP command lines**. A caller that passes an attacker-influenced sender or recipient address into `mail()`/`rcpt()` (or `vrfy()`/`expn()`) therefore allows **SMTP command injection** (CWE-93 / CWE-77): the attacker can smuggle arbitrary SMTP verbs such as `MAIL FROM`, `RCPT TO`, `RSET`, `DATA`, or `AUTH` into the session. Injected commands will cause the `SMTP` instance to hang, but all commands required to complete the envelope could be sent in one address string.\n\nThe `SMTP.sendmail()` command will pass sender and recipient addresses verbatim through to `SMTP.mail()` & `SMTP.rcpt()`, and so is also vulnerable. `SMTP.send_message()` is not affected.\n\n### Impact\n\nSeverity: medium. Type: SMTP protocol command injection (CWE-93 — Improper Neutralization of CRLF Sequences; CWE-77 — Command Injection).\n\nWhen an applicat","public_affected_ranges":["<= 5.1.0"]}],"null_published_at":"2026-11-05T19:10:21.399Z","source_updated_at":"2026-07-07T23:40:53.000Z","source_disclosed_at":"2026-07-07T23:40:52.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-04T23:34:51.634Z"}],"next_cursor":null,"snapshot_revision":"42594"}