PostCSS up to 8.5.18 PreviousMap PreviousMap.loadFile from information disclosure

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.4$0-$5k1.85

Summaryinfo

A vulnerability described as problematic has been identified in PostCSS up to 8.5.18. Affected by this issue is the function PreviousMap.loadFile of the component PreviousMap. Such manipulation of the argument from leads to information disclosure. This vulnerability is listed as CVE-2026-69153. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in PostCSS up to 8.5.18 and classified as problematic. Affected by this issue is the function PreviousMap.loadFile of the component PreviousMap. The manipulation of the argument from with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. 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. Prior to 8.5.19, if from is unset, an attacker can cause PreviousMap.loadFile() to read an unintended source-map file by supplying an absolute or directory-traversal sourceMappingURL. The resulting map’s sources and sourcesContent may then be exposed to the application. This issue is fixed in version 8.5.19.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-69153 since 08/03/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1592.

Upgrading to version 8.5.19 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.5
VulDB Meta Temp Score: 3.4

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
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: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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: PostCSS 8.5.19

Timelineinfo

08/03/2026 Advisory disclosed
08/03/2026 +0 days CVE reserved
08/03/2026 +0 days VulDB entry created
08/03/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-69153 (🔒)
GCVE (CVE): GCVE-0-2026-69153
GCVE (VulDB): GCVE-100-385628

Entryinfo

Created: 08/03/2026 19:17
Changes: 08/03/2026 19:17 (56)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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