CVE-2026-69153Public exploitNetwork attack vector

Source-map disclosure via skipped path guard

Published Aug 3, 2026 · Updated Aug 3, 2026

Path traversal in PostCSS 8.5.22 and earlier allows remote attackers to read source-map data through attacker-controlled CSS. PreviousMap.loadFile() skips its absolute-path and traversal rejection when from is unset, then readFileSync() loads the supplied .map path. Exploitation requires a consumer to process attacker-influenced CSS without from and expose result.map; disclosure is limited to valid JSON .map files and their sources or sourcesContent.

CVSS severity6.3
Medium
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Path traversal in PostCSS 8.5.22 and earlier allows remote attackers to read source-map data through attacker-controlled CSS. PreviousMap.loadFile() skips its absolute-path and traversal rejection when from is unset, then readFileSync() loads the supplied .map path. Exploitation requires a consumer to process attacker-influenced CSS without from and expose result.map; disclosure is limited to valid JSON .map files and their sources or sourcesContent.

The record

CVE
CVE-2026-69153
Published
Aug 3, 2026
Updated
Aug 3, 2026
Vendor
PostCSS
Product
PostCSS
Classifications
CWE-200, CWE-22, T1005
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=< 8.5.19

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PostCSS · PostCSSversion=< 8.5.19

Published CVSS scores

6.3GitHubCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo