CVE-2020-12639Network attack vector

Privilege elevation via unsanitized template content

Published May 4, 2020 · Updated Aug 4, 2024

Cross-site scripting in phpList before 3.5.3 allows remote attackers to elevate privileges through crafted template content. The template editor in lists/admin/template.php stored submitted content without disabling script tags or HTML event-handler attributes, allowing JavaScript to run when rendered. Exploitation requires a victim to render the malicious template, after which the script executes in that victim's browser context with the session's privileges.

CVSS severity6.1
Medium
EPSS probability0.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in phpList before 3.5.3 allows remote attackers to elevate privileges through crafted template content. The template editor in lists/admin/template.php stored submitted content without disabling script tags or HTML event-handler attributes, allowing JavaScript to run when rendered. Exploitation requires a victim to render the malicious template, after which the script executes in that victim's browser context with the session's privileges.

The record

CVE
CVE-2020-12639
Published
May 4, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 4, 2020CVE 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
4.3NIST NVDAV:N/AC:M/Au:N/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.

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

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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