What’s Vulnerable › Vulnerabilities

CVE-2026-34752: Haraka affected by DoS via `__proto__` email header

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-02 · updated 2026-10-06
• Weakness: CWE-248

Description

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.

Affected products

• Haraka: before 3.1.4 — fixed in 3.1.4

How to fix

Upgrade to a fixed version: Haraka 3.1.4. Check the vendor advisory for mitigations.

References

• https://github.com/haraka/Haraka/releases/tag/v3.1.4
• https://github.com/haraka/Haraka/security/advisories/GHSA-xph3-r2jf-4vp3

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