CVE-2021-39321Network attack vector

Authenticated PHP object injection via import_config

Published Oct 21, 2021 · Updated Mar 31, 2025

Deserialization of untrusted data in Sassy Social Share 3.3.23 allows remote authenticated users to execute code via an AJAX action. The wp_ajax_heateor_sss_import_config handler passes the user-supplied config parameter through base64 decoding and maybe_unserialize, then writes the resulting array to plugin options without capability or nonce checks. Any authenticated account able to reach the WordPress AJAX endpoint can inject PHP objects; exploitation depends on usable magic methods or gadget chains in installed code and can result in site takeover.

CVSS severity8.8
High
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization of untrusted data in Sassy Social Share 3.3.23 allows remote authenticated users to execute code via an AJAX action. The wp_ajax_heateor_sss_import_config handler passes the user-supplied config parameter through base64 decoding and maybe_unserialize, then writes the resulting array to plugin options without capability or nonce checks. Any authenticated account able to reach the WordPress AJAX endpoint can inject PHP objects; exploitation depends on usable magic methods or gadget chains in installed code and can result in site takeover.

The record

CVE
CVE-2021-39321
Published
Oct 21, 2021
Updated
Mar 31, 2025
Vendor
Heateor Support
Product
Sassy Social Share
Classifications
CWE-502, CWE-863, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 21, 2021CVE publishedPublication date reported by the CVE source.
  2. Mar 31, 2025Record 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=3.3.23

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Heateor Support · Sassy Social Shareversion=3.3.23

Published CVSS scores

8.8WordfenceCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
6.3Wordfence advisoryCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CWE-863Incorrect Authorization
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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