CVE-2025-41356Network attack vector

Browser script execution via reflected host parameter

Published Mar 31, 2026 · Updated Mar 31, 2026

Reflected XSS in Anon Proxy Server 0.104 allows remote attackers to execute JavaScript in a user's browser via a crafted URL. The /diagconnect.php endpoint returns the untrusted host parameter in generated HTML without neutralizing script content. Exploitation requires a victim to open the malicious URL, after which the script runs in the proxy site's browser context and can read session data or act as that user.

CVSS severity5.1
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Anon Proxy Server 0.104 allows remote attackers to execute JavaScript in a user's browser via a crafted URL. The /diagconnect.php endpoint returns the untrusted host parameter in generated HTML without neutralizing script content. Exploitation requires a victim to open the malicious URL, after which the script runs in the proxy site's browser context and can read session data or act as that user.

The record

CVE
CVE-2025-41356
Published
Mar 31, 2026
Updated
Mar 31, 2026
Vendor
Anon Proxy Server
Product
Anon Proxy Server
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 31, 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=0.104

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Anon Proxy Server · Anon Proxy Serverversion=0.104

Published CVSS scores

5.1INCIBECVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A: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 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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001Malicious Link

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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