CVE-2026-27808 json
Mailpit is Vulnerable to Server-Side Request Forgery (SSRF) via Link Check API
published 2026-02-25 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-8775 , GHSA-mpf7-p9x7-96r3 , GO-2026-4558
- cvss
- 5.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
Mailpit is an email testing tool and API for developers. Prior to version 1.29.2, the Link Check API (/api/v1/message/{ID}/link-check) is vulnerable to Server-Side Request Forgery (SSRF). The server performs HTTP HEAD requests to every URL found in an email without validating target hosts or filtering private/internal IP addresses. The response returns status codes and status text per link, making this a non-blind SSRF. In the default configuration (no authentication on SMTP or API), this is fully exploitable remotely with zero user interaction. This is the same class of vulnerability that was fixed in the HTML Check API (CVE-2026-23845 / GHSA-6jxm-fv7w-rw5j) and the screenshot proxy (CVE-2026-21859 / GHSA-8v65-47jx-7mfr), but the Link Check code path was not included in either fix. Version 1.29.2 fixes this vulnerability.
Patch / fix
- go github.com/axllent/mailpit 1.29.2
- axllent mailpit 1.29.2
- govulncheck-vulndb openSUSE Leap 15.6 0.0.20260317T205859-150000.1.152.1
suse advisories SUSE-SU-2026:1042-1
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 8 mo ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/axllent/mailpit/security/advisories/GHSA-mpf7-p9x7-96r3 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N |
| GitHub | 3.1 | 5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N |
| NVD | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/axllent/mailpit | <1.29.2 |
1.29.2 |
Affected products
- axllent mailpit
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
github.com
/axllent/mailpit/commit/10ad4df8cc0cd9e51dea1b4410009545eef7fbf5
web, patch
-
github.com
/axllent/mailpit/security/advisories/GHSA-mpf7-p9x7-96r3
exploit, web, vendor-advisory, advisory
-
github.com
/axllent/mailpit/releases/tag/v1.29.2
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2026-27808
advisory
-
github.com
/axllent/mailpit
package
Sources
- CVE List CVE-2026-27808
- GitHub Advisory GHSA-mpf7-p9x7-96r3
- NVD CVE-2026-27808
- OSV GO-2026-4558
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.