dbcve.org
MailpitApplication · Axllent

CVE-2026-45712

MEDIUM · 5.9 CVSS v3.1 Developing Published 2026-07-20
Fix available
A fix is available. Upgrade to 1.30.0 or later.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click 4 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Mailpit is an email testing tool and API for developers. Prior to version 1.30.0, the screenshot/print proxy (/proxy?data=…) maintains a package-level assets map[string]MessageAssets cache, but reads the map without holding assetsMutex while a long-running cleanup goroutine and (re-entrant) CSS-rewriting code path concurrently write to it under the lock. When the unsynchronized read coincides with a synchronized write, Go's runtime raises fatal error: concurrent map read and map write — a runtime.throw that is not recoverable by http.Server's handler-panic recover. The whole Mailpit process exits, taking the SMTP, POP3 and HTTP listeners down with it. Version 1.30.0 contains a patch.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · low confidence
Developing — this CVE was published recently and its authoritative NVD entry is still being established, so we're holding a technical summary until the source data settles rather than publish something unreliable. Re-checking after 2026-08-03.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
MailpitApplication
Affected:< 1.30.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.30.0 or later
Fixed in 1.30.0
Recommended fix High confidence

version 1.30.0

  1. Check current Mailpit version using `mailpit --version` or checking the running container/service
  2. Review the Mailpit 1.30.0 release notes for any configuration or behavioral changes
  3. Backup Mailpit configuration and data directories before upgrading
  4. Upgrade Mailpit to version 1.30.0 using your deployment method (e.g., Docker: `docker pull axllent/mailpit:v1.30.0`, package manager, or binary download)
  5. Restart the Mailpit service
  6. Verify the new version is running with `mailpit --version`
  7. Test that SMTP, POP3, and HTTP listeners are operational
Caveat None documented in the provided description; this is a bugfix release addressing a race condition

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-45712 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data