CVE-2025-58998Network attack vectorHinoki check available

Unauthenticated object injection via registration deserialization

Published Nov 6, 2025 · Updated Nov 6, 2025

PHP object injection in WebSharks s2Member 250701 and earlier allows remote attackers to inject objects through multisite registration. The plugin deserializes untrusted custom registration-field data, but public advisories do not identify the responsible function or parameter. No s2Member POP chain is known; file deletion, data retrieval, or code execution requires a usable chain from another installed plugin or theme.

CVSS severity9.8
Critical
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

PHP object injection in WebSharks s2Member 250701 and earlier allows remote attackers to inject objects through multisite registration. The plugin deserializes untrusted custom registration-field data, but public advisories do not identify the responsible function or parameter. No s2Member POP chain is known; file deletion, data retrieval, or code execution requires a usable chain from another installed plugin or theme.

The record

CVE
CVE-2025-58998
Published
Nov 6, 2025
Updated
Nov 6, 2025
Vendor
Cristián Lávaque
Product
s2Member
Classifications
CWE-502, CAPEC-586, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 6, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 6, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a <=<= 250701 changes=[{"at":"250905","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cristián Lávaque · s2Memberversion=n/a <=<= 250701 changes=[{"at":"250905","status":"unaffected"}]

Published CVSS scores

9.8PatchstackCVSS: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.

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-502Deserialization of Untrusted Data
CAPEC-586Object Injection
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo