CVE-2026-63670Public exploitNetwork attack vector

Cross-site scripting via raw-text solidus parsing differential

Published Aug 17, 2026 · Updated Aug 18, 2026

Cross-site scripting in sanitize-html before 2.17.6 allows remote attackers to execute JavaScript via crafted HTML rendered to a user. The ontext handler in packages/sanitize-html/index.js appends htmlparser2 raw-text output without escaping, so a solidus-bearing textarea or xmp close leaves forbidden event-handler markup active when browsers reparse it. The default configuration is unaffected; exploitation requires textarea or xmp in allowedTags and user interaction with the rendered page.

CVSS severity6.1
Medium
EPSS probability0.29%
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 sanitize-html before 2.17.6 allows remote attackers to execute JavaScript via crafted HTML rendered to a user. The ontext handler in packages/sanitize-html/index.js appends htmlparser2 raw-text output without escaping, so a solidus-bearing textarea or xmp close leaves forbidden event-handler markup active when browsers reparse it. The default configuration is unaffected; exploitation requires textarea or xmp in allowedTags and user interaction with the rendered page.

The record

CVE
CVE-2026-63670
Published
Aug 17, 2026
Updated
Aug 18, 2026
Vendor
ApostropheCMS
Product
ApostropheCMS
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 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=< 2.17.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ApostropheCMS · ApostropheCMSversion=< 2.17.6

Published CVSS scores

6.1GitHub CNACVSS: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 exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

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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