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TI-2026-36093 Aliases CVE-2026-48824GHSA-28pq-6qxg-wg5r

Resource allocation without limits in axllent mailpit

Priority LOW 31CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-770.

Summary

Mailpit is an email testing tool and API for developers. Prior to version 1.30.1, the fix for GHSA-fpxj-m5q8-fphw (CVE-2026-45710, "Mailpit: Set a default 50MB p/m limit to prevent DoS via unlimited SMTP DATA and /api/v1/send body sizes") wrapped only `POST /api/v1/send` with `http.MaxBytesReader`. The four other Mailpit JSON-body API endpoints `PUT /api/v1/messages` (SetReadStatus), `DELETE /api/v1/messages` (DeleteMessages), `PUT /api/v1/tags` (SetMessageTags), and `POST /api/v1/message/{id}/release` (ReleaseMessage) still call `json.NewDecoder(r.Body)` directly with no body-size cap and remain reachable unauthenticated in the default `docker run axllent/mailpit:latest` deploy. An unauthenticated remote attacker can post a multi-million-element `IDs` slice and drive RSS from ~25 MiB baseline to ~450 MiB per 16 MB request body. Repeating across multiple connections accumulates the same per-request amplification per process. Version 1.30.1 contains a patch.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00541 45th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed mailpit (axllent): 1.30.1github.com/axllent/mailpit (Go): 1.30.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
axllentmailpitbefore 1.30.11.30.1Patch availableCNA
—github.com/axllent/mailpit (Go)before 1.30.11.30.1Patch availableGHSA-28pq-6qxg-wg5r
  • mailpit Vendoraxllent Affected before 1.30.1 Fixed in 1.30.1 Patch available CNA
  • github.com/axllent/mailpit (Go) Vendor— Affected before 1.30.1 Fixed in 1.30.1 Patch available GHSA-28pq-6qxg-wg5r

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:axllent:mailpit:*:*:*:*:*:*:*:*before 1.30.1Vulnerableaxllent
  • cpe:2.3:a:axllent:mailpit:*:*:*:*:*:*:*:* Versions before 1.30.1 Vulnerable ·axllent

Remediation

  • Fix · CNA mailpit (axllent) Fixed in 1.30.1
  • Fix · GHSA-28pq-6qxg-wg5r github.com/axllent/mailpit (Go) Fixed in 1.30.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-48824
  2. 2026-10-03 Alias added: GHSA-28pq-6qxg-wg5r

References

Exploit 1

Advisory 1

Other 2

  • TI-2026-22161 Mailpit is Vulnerable to Server-Side Request Forgery (SSRF) via Link Check API CVSS 3.1HIGH 8.6
  • TI-2026-33452 Mailpit: Unauthenticated remote memory-exhaustion DoS via unlimited SMTP DATA and /api/v1/send body sizes CVSS 3.1HIGH 7.5
  • TI-2026-33450 Mailpit: Path traversal & arbitrary file write in mailpit dump --http via attacker-controlled message IDs CVSS 3.1HIGH 8.2
  • TI-2026-17561 Mailpit Proxy Endpoint is Vulnerable to Server-Side Request Forgery (SSRF) CVSS 3.1MEDIUM 5.8
  • TI-2026-19194 Mailpit has SMTP Header Injection via Regex Bypass CVSS 3.1MEDIUM 5.3
  • TI-2026-33451 Race condition in axllent mailpit CVSS 3.1MEDIUM 5.9
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences