What is CVE-2026-34752?

CVE-2026-34752 is a high-severity vulnerability in Haraka, classified under CWE-248. CVSS score: 7.5/10. Published 2026-04-02.

How severe is CVE-2026-34752?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Haraka

CVE-2026-34752

Haraka is a Node.js mail server. Prior to version 3.1.4, sending an email with __proto__: as a header name crashes the Haraka worker process. This issue has been patched in version 3.1.4.

EPSS: 0.004 (35.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Haraka — versions < 3.1.4
Haraka_project Haraka

Weakness classification (CWE)

CWE-248

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
security-advisories@github.com (x_refsource_MISC, Release Notes)

Frequently asked questions

What is CVE-2026-34752?: CVE-2026-34752 is a high-severity vulnerability in Haraka, classified under CWE-248. CVSS score: 7.5/10. Published 2026-04-02.
How severe is CVE-2026-34752?: High severity. CVSS v3 base score is 7.5 out of 10.