CVE-2026-61784Network attack vectorHinoki check available

Cross-site scripting via unencoded attribute values

Published Sep 24, 2026 · Updated Sep 24, 2026

Cross-site scripting in xhtml-purifier before 0.4.3 allows remote attackers to inject browser-executed JavaScript through allowed attributes. The attributeString function concatenates unencoded values into double-quoted attributes, so an embedded quote creates an event-handler attribute that survives sanitization. Exploitation requires an application to accept attacker-controlled HTML, sanitize it with the library, and render the returned markup in a browser.

CVSS severity6.1
Medium
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Cross-site scripting in xhtml-purifier before 0.4.3 allows remote attackers to inject browser-executed JavaScript through allowed attributes. The attributeString function concatenates unencoded values into double-quoted attributes, so an embedded quote creates an event-handler attribute that survives sanitization. Exploitation requires an application to accept attacker-controlled HTML, sanitize it with the library, and render the returned markup in a browser.

The record

CVE
CVE-2026-61784
Published
Sep 24, 2026
Updated
Sep 24, 2026
Vendor
Charlie Stigler
Product
xhtml-purifier
Classifications
CWE-79, CWE-116, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 24, 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=< 0.4.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Charlie Stigler · xhtml-purifierversion=< 0.4.3

Published CVSS scores

6.1GitHubCVSS: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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 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')
CWE-116Improper Encoding or Escaping of Output
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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