CVE-2023-5771Network attack vector

Stored XSS via crafted email subject

Published Nov 6, 2023 · Updated Sep 4, 2024

Stored XSS in Proofpoint Enterprise Protection allows remote attackers to execute script in AdminUI through crafted email subjects. AdminUI renders HTML carried in a quarantined message's subject without neutralizing it, causing stored script content to run when the message is viewed. Affected releases precede patch 4795 or 4796 on their respective branches; no product account is required, but an administrator must view the message.

CVSS severity6.1
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Proofpoint Enterprise Protection allows remote attackers to execute script in AdminUI through crafted email subjects. AdminUI renders HTML carried in a quarantined message's subject without neutralizing it, causing stored script content to run when the message is viewed. Affected releases precede patch 4795 or 4796 on their respective branches; no product account is required, but an administrator must view the message.

The record

CVE
CVE-2023-5771
Published
Nov 6, 2023
Updated
Sep 4, 2024
Vendor
Proofpoint
Product
Proofpoint Enterprise Protection
Classifications
CWE-79, T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 6, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.0 <8.18.6
  2. Affected versionversion=8.18.6 <patch 4795 changes=[{"at":"patch 4795","status":"unaffected"}]
  3. Affected versionversion=8.20.0 <patch 4796 changes=[{"at":"patch 4796","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Proofpoint · Proofpoint Enterprise Protectionversion=8.0 <8.18.6; version=8.18.6 <patch 4795 changes=[{"at":"patch 4795","status":"unaffected"}]; version=8.20.0 <patch 4796 changes=[{"at":"patch 4796","status":"unaffected"}]

Published CVSS scores

6.1Proofpoint Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204User Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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