CVE-2021-38371: High severity Exim Exim vulnerability

Published Aug 10, 2021
·
Updated

The STARTTLS feature in Exim through 4.94.2 allows response injection (buffering) during MTA SMTP sending.

Affected Software

7 affected componentsFixes available
ubuntu/exim4<4.90.1-1ubuntu1.10+
4.90.1-1ubuntu1.10+
ubuntu/exim4<4.93-13ubuntu1.11
4.93-13ubuntu1.11
ubuntu/exim4<4.82-3ubuntu2.4+
4.82-3ubuntu2.4+
ubuntu/exim4<4.95
4.95
ubuntu/exim4<4.86.2-2ubuntu2.6+
4.86.2-2ubuntu2.6+
debian/exim4<=4.94.2-7+deb11u3
4.96-15+deb12u54.98-1
Exim Exim<=4.94.2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/exim4 to a version that resolves this vulnerability.

    Fixed in 4.90.1-1ubuntu1.10+
  2. Upgrade

    Upgrade ubuntu/exim4 to a version that resolves this vulnerability.

    Fixed in 4.93-13ubuntu1.11
  3. Upgrade

    Upgrade ubuntu/exim4 to a version that resolves this vulnerability.

    Fixed in 4.82-3ubuntu2.4+
  4. Upgrade

    Upgrade ubuntu/exim4 to a version that resolves this vulnerability.

    Fixed in 4.95
  5. Upgrade

    Upgrade ubuntu/exim4 to a version that resolves this vulnerability.

    Fixed in 4.86.2-2ubuntu2.6+
  6. Upgrade

    Upgrade debian/exim4 to a version that resolves this vulnerability.

    Fixed in 4.96-15+deb12u5Fixed in 4.98-1

Event History

Aug 10, 2021
CVE Published
via Ubuntu·12:00 AM
CVE Published
via MITRE·02:06 PM
Data Sourced
via MITRE·02:06 PM
Description
Data Sourced
via NVD·03:15 PM
DescriptionSeverityWeaknessAffected Software
Jul 10, 2024
Data Sourced
via Launchpad·04:41 AM
Description

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-38371?

CVE-2021-38371 is a vulnerability in Exim, a popular mail transfer agent software, that allows response injection (buffering) during MTA SMTP sending.

2

What is the severity of CVE-2021-38371?

CVE-2021-38371 has a high severity with a CVSS score of 7.5.

3

How does CVE-2021-38371 affect Exim?

CVE-2021-38371 affects Exim versions up to and including 4.94.2, exposing them to response injection (buffering) during MTA SMTP sending.

4

How can I fix CVE-2021-38371?

To fix CVE-2021-38371, users are advised to update their Exim software to version 4.94.3 or later, which includes a patch for this vulnerability.

5

Where can I find more information about CVE-2021-38371?

More information about CVE-2021-38371 can be found on the official Exim website and the CVE-2021-38371.txt security advisory.

Company

Resources

Contact

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