CVE-2026-67447
MEDIUMDescription
Mailpit is an email testing tool and API for developers. From 1.30.0 until 1.30.5, Mailpit's internal/smtpd/smtpd.go readData() function calls bufio.Reader.ReadBytes before applying the len(data)+len(line) size check to the completed SMTP DATA line against Server.MaxSize. An unauthenticated SMTP client can send a single line larger than the configured MaxMessageSize, causing the full line to be allocated before Mailpit returns the 552 5.3.4 rejection. This post-fix gap remains after normal multi-line DATA accumulation was bounded, and concurrent oversized lines can create substantial memory pressure beyond the configured message-size cap. This issue is fixed in version 1.30.5.
How to fix
No published remediation has been found for this vulnerability's affected products yet.
Mitigation guidance may be in the linked vendor advisories in the References section below.
TridentStack Control tracks known vulnerabilities across your Windows, macOS, and Linux fleet and shows the fix as soon as one is published. See how it works
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Exploit Intelligence
Low risk: more likely to be exploited than 30% of all known CVEs.
References
Related Vulnerabilities
Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2023-50387 | High | 7.5 | 100% | - | Fix |
| CVE-2019-11478 | Medium | 5.3 | 93% | - | Fix |
| CVE-2019-11479 | High | 7.5 | 92% | - | Fix |
| CVE-2024-27316 | High | 7.5 | 91% | - | Fix |
| CVE-2022-30522 | High | 7.5 | 90% | - | Fix |
| CVE-2019-9515 | High | 7.5 | 87% | - | Fix |
Common questions
How do I fix CVE-2026-67447?
No published fix for CVE-2026-67447 has been found yet. Check the linked vendor advisories for guidance as it becomes available.
Is CVE-2026-67447 being actively exploited?
Not that we know of. CVE-2026-67447 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.37% is the estimated probability that it will be exploited in the next 30 days. That is higher than 30% of all scored CVEs.
How severe is CVE-2026-67447?
CVE-2026-67447 has a CVSS v3 base score of 5.3, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
Embed a live status badge for CVE-2026-67447
Markdown
[](https://tridentstack.com/cve/CVE-2026-67447)HTML
<a href="https://tridentstack.com/cve/CVE-2026-67447"><img src="https://tridentstack.com/cve/badge/CVE-2026-67447.svg" alt="CVE-2026-67447"></a>Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-08-21.