What is the CVSS score of CVE-2026-30830?

CVE-2026-30830 has a CVSS 3.1 base score of 6.1 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Defuddle are affected by CVE-2026-30830?

CVE-2026-30830 presents moderate security risk, a cross-site scripting vulnerability rated CVSS 6.1. Attackers could inject scripts to steal sessions or perform actions as authenticated users.. A patch is available.

Is there a public PoC exploit available for CVE-2026-30830?

Yes, a public proof-of-concept exploit is available for CVE-2026-30830. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-30830?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Defuddle CVE-2026-30830

MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-03-07 security-advisories@github.com

GHSA-5mq8-78gm-pjmq

XSS Defuddle

6.1

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

6.1 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:55 vuln.today

PoC Detected

Mar 11, 2026 - 18:50 vuln.today

Public exploit code

Patch released

Mar 11, 2026 - 18:50 nvd

Patch available

CVE Published

Mar 07, 2026 - 06:16 nvd

MEDIUM 6.1

DescriptionGitHub Advisory

Defuddle cleans up HTML pages. Prior to version 0.9.0, the _findContentBySchemaText method in src/defuddle.ts interpolates image src and alt attributes directly into an HTML string without escaping. An attacker can use a " in the alt attribute to break out of the attribute context and inject event handler. This issue has been patched in version 0.9.0.

AnalysisAI

Defuddle versions prior to 0.9.0 fail to properly escape image attributes in HTML processing, allowing attackers to inject malicious event handlers through specially crafted alt text containing quote characters. Public exploit code exists for this cross-site scripting vulnerability. The vulnerability affects all users of Defuddle before version 0.9.0, and a patch is available.

Technical ContextAI

Classified as CWE-79 (Cross-site Scripting (XSS)). Affects Defuddle. Defuddle cleans up HTML pages. Prior to version 0.9.0, the _findContentBySchemaText method in src/defuddle.ts interpolates image src and alt attributes directly into an HTML string without escaping. An attacker can use a " in the alt attribute to break out of the attribute context and inject event handler. This issue has been patched in version 0.9.0.

RemediationAI

A vendor patch is available — apply it immediately. Fixed in version 0.9.0.. Implement output encoding and Content Security Policy headers. Restrict network access to the affected service where possible.