CVE-2026-33386

Browser script execution via plaintext plugin fetch

Published May 29, 2026 · Updated May 29, 2026

Cross-site scripting in OpenSolution Quick.Cms 6.8 and earlier allows man-in-the-middle attackers to execute script in an administrator's browser. The plugin page fetches its plugin list from opensolution.org over plaintext HTTP, then renders the returned HTML without neutralizing script. Exploitation requires control of the network path and an administrator to open the plugin page; code runs only in that browser context.

CVSS severity2.3
Low
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in OpenSolution Quick.Cms 6.8 and earlier allows man-in-the-middle attackers to execute script in an administrator's browser. The plugin page fetches its plugin list from opensolution.org over plaintext HTTP, then renders the returned HTML without neutralizing script. Exploitation requires control of the network path and an administrator to open the plugin page; code runs only in that browser context.

The record

CVE
CVE-2026-33386
Published
May 29, 2026
Updated
May 29, 2026
Vendor
OpenSolution
Product
Quick.Cms
Classifications
CWE-79, T1189
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 29, 2026CVE publishedPublication date reported by the CVE source.
  2. May 29, 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=0 <=6.8

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

OpenSolution · Quick.Cmsversion=0 <=6.8

Published CVSS scores

2.3CERT.PLCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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

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Your stack

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