PatchTheCVECVE-2026-34752: Haraka is a Node.js mail server
CVE-2026-34752 is a high-severity flaw (CVSS 7.5) affecting haraka. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- High severity
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 63%) |
| CISA exploited list | No |
| Weakness | CWE-248 |
| Published | 2026-04-02 |
| Last modified | 2026-10-06 |
Last updated 2026-10-06 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-34752?
haraka: upgrade to 3.1.4. Exact commands for each OS are on this page.
Is CVE-2026-34752 being exploited?
CVE-2026-34752 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-34752 affect?
CVE-2026-34752 affects haraka. Severity is high (CVSS 7.5). 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.
How urgent is CVE-2026-34752?
Priority 46/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action