CVE-2020-28017

9.8 CRITICAL 37% exploit odds Fix listed Memory safety

What it is

Exim 4 before 4.94.2 allows Integer Overflow to Buffer Overflow in receive_add_recipient via an e-mail message with fifty million recipients. NOTE: remote exploitation may be difficult because of resource consumption.

At a glance

Exploitability: Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
Exploit odds: 36.6% chance of exploitation in the next 30 days (EPSS). Higher than most.
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2020-10-30 00:00 UTC ReservedThe CVE id was reserved by its CNA
2021-05-06 13:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-06-17 03:10 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 36.6% in the next 30 days (EPSS).
Severity: 9.8 CRITICAL (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2021-05-06 13:15 UTC
Last modified: 2026-06-17 03:10 UTC
Exploit probability: 36.6% · EPSS, next 30 days
Weakness: CWE-190 · Integer overflow
Record status: Modified

Affected

Exim < 4.94.1

Attack profile CVSS 3.1 · 9.8

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2020-28017.md and follow it. Check whether this project is affected by CVE-2020-28017. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

· More options · Status badge

Download Square Reddit

Fix and advisories

References

NVD record · CVE.org record