CVE-2026-69153

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.

CVSS v4.0

6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v4.0

6.3 MEDIUMCVSS: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 v3.1

5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

0.45% chance of exploitation in the next 30 days, 38th percentile

Published

2026-08-03

Proof-of-concept exploits (1)

• advisories/GHSA-fxqj-rqcc-2cmp

References

• CVE Record
• NVD entry

Related

• CVE-2026-69152
• CVE-2026-69160
• CVE-2026-69148
• CVE-2026-69192
• CVE-2026-69146
• CVE-2026-69198