CVE-2026-6909Public exploitNetwork attack vector

Reflected XSS via unescaped new_version parameter

Published May 11, 2026 · Updated May 11, 2026

Reflected XSS in ATutor 2.2.4 allows remote attackers to execute JavaScript in a victim's browser through /install/upgrade.php. The endpoint reads the new_version POST parameter and renders it unescaped in upgrade_header.php headings and navigation text. Exploitation requires the victim to submit a crafted request while the browser can reach an installation whose /install/ directory remains accessible.

CVSS severity7.5
High
EPSS probability0.39%
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 ATutor 2.2.4 allows remote attackers to execute JavaScript in a victim's browser through /install/upgrade.php. The endpoint reads the new_version POST parameter and renders it unescaped in upgrade_header.php headings and navigation text. Exploitation requires the victim to submit a crafted request while the browser can reach an installation whose /install/ directory remains accessible.

The record

CVE
CVE-2026-6909
Published
May 11, 2026
Updated
May 11, 2026
Vendor
ATutor
Product
ATutor
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 11, 2026CVE publishedPublication date reported by the CVE source.
  2. May 11, 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=2.2.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ATutor · ATutorversion=2.2.4

Published CVSS scores

7.5AFINECVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/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.

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No observations available

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

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001Malicious Link

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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