CVE-2026-73646
Description
A flaw was found in PostCSS. An attacker can exploit a path traversal vulnerability by providing specially crafted sourceMappingURL values in untrusted CSS files. This allows the attacker to disclose sensitive sourcesContent from arbitrary .map files accessible on the system, leading to information disclosure.
Statement
Important severity is assigned to this flaw because an unauthenticated remote attacker could read arbitrary source map files from the host filesystem without privileges if an application processes untrusted stylesheets. Within Red Hat products, PostCSS is bundled primarily inside web console frontends, build-time pipelines, and developer environments. Practical exposure is limited because most deployments only parse internal, developer-authored styles rather than accepting arbitrary user-supplied style sheets. Furthermore, environments that do not process untrusted external styling or that run purely as static client assets are not exposed to remote data disclosure.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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