CVE-2023-5770

HTML injection in email body through email subject

MEDIUM
5.4
CVSS Score
Published: January 9, 2024 at 10:02 PM UTC
Updated: June 17, 2026 at 06:49 AM UTC
1 product affected across 1 vendorEnterprise Protection

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Severity
MEDIUM5.4
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

Proofpoint Enterprise Protection contains a vulnerability in the email delivery agent that allows an unauthenticated attacker to inject improperly encoded HTML into the email body of a message through the email subject. The vulnerability is caused by inappropriate encoding when rewriting the email before delivery.This issue affects Proofpoint Enterprise Protection: from 8.20.2 before patch 4809, from 8.20.0 before patch 4805, from 8.18.6 before patch 4804 and all other prior versions.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

8.0 ≤ v < 8.18.68.18.6 ≤ v < patch 48048.20.0 ≤ v < patch 48058.20.2 ≤ v < patch 48098.08.18.68.20.08.20.2
Affected range stops below 8.18.6, so it looks safe — our inference, not a vendor statement
Affected range stops below patch 4804, so it looks safe — our inference, not a vendor statement
Affected range stops below patch 4805, so it looks safe — our inference, not a vendor statement
Affected range stops below patch 4809, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-838

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