PT-2026-55207 · Mailpit · Mailpit

CVE-2026-48824

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Published

2026-07-01

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Updated

2026-07-30

CVSS v3.1

5.3

Medium

VectorAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Name of the Vulnerable Software and Affected Versions Mailpit versions prior to 1.30.1
Description An incomplete fix for a previous denial-of-service issue left several API endpoints without body-size limits. An unauthenticated remote attacker can send a specially crafted JSON request containing a multi-million-element IDs slice to exhaust system memory (RSS), leading to a denial-of-service. This memory amplification occurs because the application calls json.NewDecoder(r.Body) directly without a size cap, causing the memory usage to grow linearly with the payload size.
API Endpoints:
  • PUT /api/v1/messages (SetReadStatus)
  • DELETE /api/v1/messages (DeleteMessages)
  • PUT /api/v1/tags (SetMessageTags)
  • POST /api/v1/message/{id}/release (ReleaseMessage)
Vulnerable Parameters or Variables:
  • IDs
Recommendations Update Mailpit to version 1.30.1 or later. As a temporary workaround, restrict access to the affected API endpoints to trusted networks to minimize the risk of unauthenticated exploitation.

Exploit

Fix

Allocation of Resources Without Limits

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Weakness Enumeration

Related Identifiers

CVE-2026-48824
GHSA-28PQ-6QXG-WG5R
GO-2026-5868
OPENSUSE-SU-2026:21483-1

Affected Products

Mailpit