darylldoyle svg-sanitizer up to 0.21.x Attribute Name cleanXlinkHrefs cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in darylldoyle svg-sanitizer up to 0.21.x. This vulnerability affects the function cleanXlinkHrefs of the component Attribute Name Handler. Performing a manipulation results in cross site scripting. This vulnerability is known as CVE-2025-55166. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in darylldoyle svg-sanitizer up to 0.21.x. This affects the function cleanXlinkHrefs of the component Attribute Name Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on confidentiality, and integrity. The summary by CVE is:

savg-sanitizer is a PHP SVG/XML sanitizer. Prior to version 0.22.0, the sanitization logic in the cleanXlinkHrefs method only searches for lower-case attribute name, which allows to by-pass the isHrefSafeValue check. As a result this allows cross-site scripting or linking to external domains. This issue has been patched in version 0.22.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2025-55166 since 08/07/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 0.22.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-1834). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • TYPO3 Core
  • Open Source ILIAS

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: svg-sanitizer 0.22.0

Timelineinfo

08/07/2025 CVE reserved
08/12/2025 +5 days Advisory disclosed
08/12/2025 +0 days VulDB entry created
01/21/2026 +162 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2025-55166 (🔒)
GCVE (CVE): GCVE-0-2025-55166
GCVE (VulDB): GCVE-100-319575
CERT Bund: WID-SEC-2025-1834 - TYPO3 Core: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

Entryinfo

Created: 08/12/2025 19:11
Updated: 01/21/2026 09:46
Changes: 08/12/2025 19:11 (68), 08/15/2025 06:38 (7), 01/21/2026 09:46 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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