CVE-2026-66296Public exploitNetwork attack vector

Reflected XSS via unescaped validation error rendering

Published Aug 3, 2026 · Updated Aug 3, 2026

Reflected XSS in Oaskit before 0.14.1 allows remote attackers to execute JavaScript via a crafted request-validation failure. Oaskit.ErrorHandler.Default inserts query-object keys and raw Content-Type values into its HTML error page without HTML escaping. A victim must follow a crafted GET link; the resulting script runs in the application's origin and can access session cookies and same-origin data.

CVSS severity5.1
Medium
EPSS probability0.24%
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 Oaskit before 0.14.1 allows remote attackers to execute JavaScript via a crafted request-validation failure. Oaskit.ErrorHandler.Default inserts query-object keys and raw Content-Type values into its HTML error page without HTML escaping. A victim must follow a crafted GET link; the resulting script runs in the application's origin and can access session cookies and same-origin data.

The record

CVE
CVE-2026-66296
Published
Aug 3, 2026
Updated
Aug 3, 2026
Vendor
Ludovic Dem
Product
Oaskit
Classifications
CWE-80, CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1.0 <0.14.1
  2. Affected versionversion=552de8ca0ff60617bea58bcafa451892d61a161c <b70c6b2eaf0b11bdd0bbb21b8a87dbb3d46918a1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ludovic Dem · Oaskitversion=0.1.0 <0.14.1; version=552de8ca0ff60617bea58bcafa451892d61a161c <b70c6b2eaf0b11bdd0bbb21b8a87dbb3d46918a1

Published CVSS scores

5.1EEFCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1GitHubCVSS: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.

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-80Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
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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