CVE-2020-36326Network attack vector

Code execution via premature Phar path processing

Published Apr 28, 2021 · Updated Aug 4, 2024

Object injection in PHPMailer 6.1.8 through 6.4.0 allows attackers to execute code through an unfiltered Phar attachment path. In fileIsAccessible(), file_exists processes the supplied path before isPermittedPath rejects its URL scheme, triggering Phar metadata deserialization. Reachability requires calling code to pass an unfiltered attacker-controlled attachment path; successful exploitation runs code in the host PHP process.

CVSS severity9.8
Critical
EPSS probability3.09%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Object injection in PHPMailer 6.1.8 through 6.4.0 allows attackers to execute code through an unfiltered Phar attachment path. In fileIsAccessible(), file_exists processes the supplied path before isPermittedPath rejects its URL scheme, triggering Phar metadata deserialization. Reachability requires calling code to pass an unfiltered attacker-controlled attachment path; successful exploitation runs code in the host PHP process.

The record

CVE
CVE-2020-36326
Published
Apr 28, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-641, CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 28, 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8GitHub Advisory DatabaseCVSS: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 exploitUnconfirmed

Weakness, pattern, technique

CWE-641Improper Restriction of Names for Files and Other Resources
CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

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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