CVE-2026-45712: 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]MessageAsse

mediumCVSS 5.9CVE-2026-45712

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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 5.9
Published: 2026-07-20
Last updated: 2026-07-21
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-45712

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-457120.25% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 16% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-45712	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[UPDATE] [medium] MailPit: Multiple vulnerabilitiescert-bund

Recent advisories for Mailpit is an

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

medium[NEW] [medium] MailPit: Vulnerability allows disclosure of informationcert-bund · 2026-07-29
medium[UPDATE] [medium] MailPit: Vulnerability allows Denial of Servicecert-bund · 2026-07-21
medium[UPDATE] [medium] MailPit: Multiple vulnerabilitiescert-bund · 2026-07-21
mediumCVE-2026-48824: Mailpit is an email testing tool and API for developers. Prior to version 1.30.1, the fix for …nvd · 2026-07-20
highCVE-2026-45713: Mailpit is an email testing tool and API for developers. Prior to version 1.30.0, the Mailpit …nvd · 2026-07-20
mediumCVE-2026-45711: Mailpit is an email testing tool and API for developers. Prior to version 1.30.0, the mailpit …nvd · 2026-07-20