CVE-2021-38371

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Published Aug 10, 2021 CVSS 3.1 · 7.5 High EPSS 2.0% KEV · Not listed

Description

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

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source	ID	Title
Debian DLA	DLA-3938-1	exim4 security update
EUVD	EUVD-2021-24824	The STARTTLS feature in Exim through 4.94.2 allows response injection (buffering) during MTA SMTP sending.
Ubuntu USN	USN-6881-1	Exim vulnerability

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: 2.0% (1.996% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://lists.debian.org/debian-lts-announce/2024/10/msg00029.html
https://nostarttls.secvuln.info
https://www.exim.org
https://www.exim.org/static/doc/security/CVE-2021-38371.txt

History

Nov 3, 2025 10:30 PM Added references View changes

Type	Values Removed	Values Added
References		https://lists.debian.org/debian-lts-announce/2024/10/msg00029.html

Subscriptions

Exim Exim

Weaknesses

CWE-74

Sources

CVE record Updated: Nov 3, 2025, 9:45 PM

Status: PUBLISHED
Assigner: mitre
Published: Aug 10, 2021, 2:06 PM
Updated: Nov 3, 2025, 9:45 PM
Reserved: Aug 10, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 4:01 AM

Status: Modified
Published: Aug 10, 2021, 3:15 PM
Modified: Jun 17, 2026, 4:01 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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