CVE-2020-23209Public exploitNetwork attack vector

Stored script execution via list description

Published Jul 1, 2021 · Updated Aug 4, 2024

Stored cross-site scripting in phplist 3.5.3 allows remote authenticated users to execute arbitrary scripts via the List Description field. The Edit A List module stores attacker-supplied description content and later renders it without HTML entity encoding, causing script markup to execute in a viewer's browser. An authenticated account and a victim viewing the affected list are required; the script can read session data or perform actions as that viewer.

CVSS severity5.4
Medium
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in phplist 3.5.3 allows remote authenticated users to execute arbitrary scripts via the List Description field. The Edit A List module stores attacker-supplied description content and later renders it without HTML entity encoding, causing script markup to execute in a viewer's browser. An authenticated account and a victim viewing the affected list are required; the script can read session data or perform actions as that viewer.

The record

CVE
CVE-2020-23209
Published
Jul 1, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 1, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.4NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NVDAV:N/AC:M/Au:S/C:N/I:P/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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

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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