CVE-2026-55573Public exploitNetwork attack vectorHinoki check available

Unauthenticated code execution via installer object deserialization

Published Oct 14, 2026 · Updated Oct 14, 2026

Unsafe deserialization in e107 Inc e107 before 2.3.7 allows remote attackers to execute PHP functions via install.php POST requests. The installer passes decoded previous_steps input to unserialize() without restricting classes, and string coercion of the resulting site_path object invokes an attacker-controlled callable through bundled PumpStream code. Exploitation requires reachable install.php, which remains accessible after default installation, and executes with the web server process's privileges.

CVSS severity9.8
Critical
EPSS probability0.60%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Unsafe deserialization in e107 Inc e107 before 2.3.7 allows remote attackers to execute PHP functions via install.php POST requests. The installer passes decoded previous_steps input to unserialize() without restricting classes, and string coercion of the resulting site_path object invokes an attacker-controlled callable through bundled PumpStream code. Exploitation requires reachable install.php, which remains accessible after default installation, and executes with the web server process's privileges.

The record

CVE
CVE-2026-55573
Published
Oct 14, 2026
Updated
Oct 14, 2026
Vendor
e107 Inc
Product
e107
Classifications
CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 14, 2026Record 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=< 2.3.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

e107 Inc · e107version=< 2.3.7

Published CVSS scores

9.8GitHubCVSS: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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

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Technologies

Your stack

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