{"cve":"CVE-2026-45713","nvd":{"published":"2026-07-20T16:17:00.610","modified":"2026-10-24T20:10:00.137","status":"Analyzed","description":"Mailpit is an email testing tool and API for developers. Prior to version 1.30.0, the Mailpit SMTP server has a Server.MaxSize int field that controls the maximum allowed DATA payload size, but the field is never assigned anywhere outside test code, leaving it at Go's zero value (0 ⇒ \"no limit\"). The same applies to the HTTP /api/v1/send endpoint, whose request body is decoded with json.NewDecoder(r.Body) and no http.MaxBytesReader. Because Mailpit's default listeners bind [::]:1025 (SMTP) and [::]:8025 (HTTP), with no authentication required on either, a single network-reachable attacker can push an arbitrarily large message into Mailpit and watch RAM consumption spike with a ~7-10× amplification factor (raw frame → enmime envelope tree → search-text index → zstd-encoded write to SQLite). Repeating the attack — or running it concurrently from multiple connections — drives the process to OOM-kill. Version 1.30.0 contains a patch.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400","CWE-770"],"references":["https://github.com/axllent/mailpit/releases/tag/v1.30.0","https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw","https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw"],"products":["axllent:mailpit"],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-45713","score":0.00607,"percentile":0.48738,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-fpxj-m5q8-fphw","url":"https://osv.dev/vulnerability/GHSA-fpxj-m5q8-fphw","summary":"Mailpit: Unauthenticated remote memory-exhaustion DoS via unlimited SMTP DATA and /api/v1/send body sizes","modified":"2026-09-02T23:45:04.674047363Z","packages":[{"ecosystem":"Go","name":"github.com/axllent/mailpit","purl":"pkg:golang/github.com/axllent/mailpit","ranges":["<1.30.0"],"fixed":["1.30.0"]}]},{"id":"GO-2026-5376","url":"https://osv.dev/vulnerability/GO-2026-5376","summary":"Mailpit: Unauthenticated remote memory-exhaustion DoS via unlimited SMTP DATA and /api/v1/send body sizes in github.com/axllent/mailpit","modified":"2026-06-25T19:45:19.114046362Z","packages":[{"ecosystem":"Go","name":"github.com/axllent/mailpit","purl":"pkg:golang/github.com/axllent/mailpit","ranges":["<1.30.0"],"fixed":["1.30.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}