{"cve":"CVE-2026-21859","nvd":{"published":"2026-01-08T00:16:00.150","modified":"2026-06-17T10:19:02.623","status":"Analyzed","description":"Mailpit is an email testing tool and API for developers. Versions 1.28.0 and below have a Server-Side Request Forgery (SSRF) vulnerability in the /proxy endpoint, allowing attackers to make requests to internal network resources. The /proxy endpoint validates http:// and https:// schemes, but it does not block internal IP addresses, enabling attackers to access internal services and APIs. This vulnerability is limited to HTTP GET requests with minimal headers. The issue is fixed in version 1.28.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","score":5.3},"cwes":["CWE-918"],"references":["https://github.com/axllent/mailpit/commit/3b9b470c093b3d20b7d751722c1c24f3eed2e19d","https://github.com/axllent/mailpit/security/advisories/GHSA-8v65-47jx-7mfr","https://github.com/axllent/mailpit/security/advisories/GHSA-8v65-47jx-7mfr"],"products":["axllent:mailpit"],"source":"nvd","synced_at":"2026-10-19T22:19:41.481987139+00:00"},"epss":{"cve":"CVE-2026-21859","score":0.00813,"percentile":0.57007,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-8v65-47jx-7mfr","url":"https://osv.dev/vulnerability/GHSA-8v65-47jx-7mfr","summary":"Mailpit Proxy Endpoint has Server-Side Request Forgery (SSRF) vulnerability","modified":"2026-02-03T03:13:30.492241Z","packages":[{"ecosystem":"Go","name":"github.com/axllent/mailpit","purl":"pkg:golang/github.com/axllent/mailpit","ranges":["<1.28.1"],"fixed":["1.28.1"]}]},{"id":"GO-2026-4284","url":"https://osv.dev/vulnerability/GO-2026-4284","summary":"Mailpit Proxy Endpoint has Server-Side Request Forgery (SSRF) vulnerability in github.com/axllent/mailpit","modified":"2026-03-03T04:57:52.801301Z","packages":[{"ecosystem":"Go","name":"github.com/axllent/mailpit","purl":"pkg:golang/github.com/axllent/mailpit","ranges":["<1.28.1"],"fixed":["1.28.1"]}]}],"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."]}