CVE-2026-8211Public exploitNetwork attack vector

Admin-only code execution via unneutralized JSP content

Published May 9, 2026 · Updated May 9, 2026

Code injection in CodeLibs Fess 15.5.0 and 15.5.1 allows remote authenticated users to execute server-side code through its JSP editor. AdminDesignAction.update writes the unneutralized content parameter to a selected JSP page, allowing supplied JSP code to execute when that page is requested. Exploitation requires the high-privilege admin-design permission and can persist code in the web application.

CVSS severity5.1
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in CodeLibs Fess 15.5.0 and 15.5.1 allows remote authenticated users to execute server-side code through its JSP editor. AdminDesignAction.update writes the unneutralized content parameter to a selected JSP page, allowing supplied JSP code to execute when that page is requested. Exploitation requires the high-privilege admin-design permission and can persist code in the web application.

The record

CVE
CVE-2026-8211
Published
May 9, 2026
Updated
May 9, 2026
Vendor
CodeLibs, Inc.
Product
Fess
Classifications
CWE-94, CWE-74, T1505.003
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 9, 2026CVE publishedPublication date reported by the CVE source.
  2. May 9, 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=15.5.0
  2. Affected versionversion=15.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

CodeLibs, Inc. · Fessversion=15.5.0; version=15.5.1

Published CVSS scores

5.1VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
5.8VulDBAV:N/AC:L/Au:M/C:P/I:P/A:P
2.0VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
4.7VulDBCVSS:3.1/AV:N/AC:L/PR:H/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1505.003Server Software Component: Web Shell

Public exploit references

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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