CVE-2026-52777Public exploitNetwork attack vector

Administrator-session code execution via unsafe Bazar deserialization

Published Sep 4, 2026 · Updated Sep 4, 2026

PHP object injection in YesWiki before 4.6.6 allows remote attackers to execute code through an administrator's authenticated session. The default Bazar import route forwards each base64-decoded importfiche value to CSVManager::importEntry, which calls unserialize() without disabling class instantiation. The route requires wiki-administrator authorization, but no CSRF token is checked, so attacker-controlled HTML can submit a gadget payload through an administrator's browser and gain a shell on the server.

CVSS severity9.4
Critical
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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 YesWiki before 4.6.6 allows remote attackers to execute code through an administrator's authenticated session. The default Bazar import route forwards each base64-decoded importfiche value to CSVManager::importEntry, which calls unserialize() without disabling class instantiation. The route requires wiki-administrator authorization, but no CSRF token is checked, so attacker-controlled HTML can submit a gadget payload through an administrator's browser and gain a shell on the server.

The record

CVE
CVE-2026-52777
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
YesWiki
Product
YesWiki
Classifications
CWE-502, CWE-352, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2026Record 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=< 4.6.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

YesWiki · YesWikiversion=< 4.6.6

Published CVSS scores

9.6GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
9.4GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA: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 exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CWE-352Cross-Site Request Forgery (CSRF)
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

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