{"items":[{"id":"NVI-00013093","kind":"vulnerability","title":"Nodemailer: Quadratic backtracking in the addressparser free-text fallback allows remote denial of service","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-v53p-9fqp-m79j"],"plain_summary":"GitHub lists this reviewed advisory for nodemailer. 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-5c7ad9691eb1c6c1308b79691d0b00f6"],"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":[{"kind":"CVSS","as_of":"2026-09-29T23:43:38.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-5c7ad9691eb1c6c1308b79691d0b00f6"}],"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-5c7ad9691eb1c6c1308b79691d0b00f6","url":"https://github.com/advisories/GHSA-v53p-9fqp-m79j","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-v53p-9fqp-m79j","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:24:25.558Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-5c7ad9691eb1c6c1308b79691d0b00f6"],"technology":"nodemailer","known_exclusions":[],"conditions_summary":"### Summary\n\nWhen `addressparser` finds no address by its strict reading, it falls back to pulling one out of the free text with `/\\s*\\b[^@\\s]+@[^\\s]+\\b\\s*/`. That pattern backtracks quadratically: `[^@\\s]+` is retried from every offset and rescans the run to the next `@` each time. A single header value holding a long whitespace-free run with no usable `@` blocks the Node.js event loop for tens of seconds.\n\nIt is cheaper to exploit than GHSA-prgh-xp8r-p3m5: 273KB is enough for ~43s, where the comment-joined shape needed ~1.5MB for ~10s.\n\n### Details\n\nThe fallback in `src/addressparser/index.ts` ran the pattern as a search. `[^@\\s]+` crosses neither whitespace nor `@`, so from each start offset it scans forward to the next `@` or to the end of the run and then fails, and the engine simply advances one character and repeats. Three shapes make every offset fail:\n\n- the run holds no `@` at all\n- the only `@` has nothing after it\n- the only `@` has nothing before it\n\nA fourth reaches it with a valid address present but placed past a long run, so the long run is walked before the match is found.\n\n### PoC\n\n```js\nconst addressparser = require('nodemailer/lib/addressparser');\nconst s = Dat","public_affected_ranges":["<= 10.0.5"]}],"null_published_at":"2026-11-01T07:29:12.919Z","source_updated_at":"2026-09-29T23:43:38.000Z","source_disclosed_at":"2026-09-29T23:43:36.000Z","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":"2026-11-01T07:24:25.558Z"}],"next_cursor":null,"snapshot_revision":"42594"}