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

April 1, 2026 (updated April 6, 2026)

Sending an email with __proto__: as a header name crashes the Haraka worker process.

References

github.com/advisories/GHSA-xph3-r2jf-4vp3
github.com/haraka/Haraka
github.com/haraka/Haraka/releases/tag/v3.1.4
github.com/haraka/Haraka/security/advisories/GHSA-xph3-r2jf-4vp3
nvd.nist.gov/vuln/detail/CVE-2026-34752

Code Behaviors & Features

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