postcss up to 8.5.9 CSS File cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in postcss up to 8.5.9. The impacted element is an unknown function of the component CSS File Handler. The manipulation results in cross site scripting. This vulnerability is identified as CVE-2026-41305. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in postcss up to 8.5.9. Affected is some unknown functionality of the component CSS File 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 integrity. CVE summarizes:

PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Versions prior to 8.5.10 do not escape `` sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML `` tags, `` in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-41305 since 04/20/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

The vulnerability scanner Nessus provides a plugin with the ID 310276 (Linux Distros Unpatched Vulnerability : CVE-2026-41305), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 8.5.10 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the databases at Tenable (310276) and CERT Bund (WID-SEC-2026-1654). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • IBM App Connect Enterprise

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.1
CNA Vector (GitHub_M): 🔒

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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Nessus ID: 310276
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-41305

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: postcss 8.5.10

Timelineinfo

04/20/2026 CVE reserved
04/24/2026 +4 days Advisory disclosed
04/24/2026 +0 days VulDB entry created
05/23/2026 +29 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-qx2v-qp2m-jg93
Status: Confirmed

CVE: CVE-2026-41305 (🔒)
GCVE (CVE): GCVE-0-2026-41305
GCVE (VulDB): GCVE-100-359256
CERT Bund: WID-SEC-2026-1654 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 04/24/2026 07:31
Updated: 05/23/2026 04:49
Changes: 04/24/2026 07:31 (65), 04/27/2026 19:18 (2), 05/23/2026 04:49 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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