CVE-2020-8547Public exploitNetwork attack vector

Administrator access via loose password-hash comparison

Published Feb 3, 2020 · Updated Aug 4, 2024

Authentication bypass in phpList 3.5.0 allows remote attackers to gain administrator access through a crafted password hash comparison. The phpListAdminAuthentication.php password-validation branch compares a computed SHA-256 hash with the stored hash using PHP's loose equality operator, causing numeric 0e-prefixed hashes to compare as equal. Exploitation requires an administrator username and a password whose digest is coerced to numeric zero, after which the resulting session exposes administrative functions.

CVSS severity9.8
Critical
EPSS probability5.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in phpList 3.5.0 allows remote attackers to gain administrator access through a crafted password hash comparison. The phpListAdminAuthentication.php password-validation branch compares a computed SHA-256 hash with the stored hash using PHP's loose equality operator, causing numeric 0e-prefixed hashes to compare as equal. Exploitation requires an administrator username and a password whose digest is coerced to numeric zero, after which the resulting session exposes administrative functions.

The record

CVE
CVE-2020-8547
Published
Feb 3, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 3, 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

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1190Exploit Public-Facing Application

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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