CVE-2020-28026

Name: CVE-2020-28026
Creator: NVD / NIST
Published: 2021-05-06T13:15:09.777+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 9.29%

Last modified Jun 17, 2026

CVE-2020-28026 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.. EPSS estimates a 9.29% chance of exploitation in the next 30 days.

Description

Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable Delivery Status Notification (DSN). Certain uses of ORCPT= can place a newline into a spool header file, and indirectly allow unauthenticated remote attackers to execute arbitrary commands as root.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

9.29%

94.7th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Exim	Exim	>= 4.00, < 4.94.2

References

https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28026-FGETS.txtThird Party Advisory
https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28026-FGETS.txtThird Party Advisory

Timeline

Published: May 6, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-28026?

How severe is CVE-2020-28026?

CVE-2020-28026 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 9.29% probability of exploitation in the next 30 days.

How do I fix CVE-2020-28026?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-28026?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST