OmniFaces is a utility library for Faces. In OmniFaces versions before 1.14.3, 2.7.33, 3.14.23, 4.7.12, and 5.4.2, CombinedResourceHandler accepts a structurally valid deflated and base64 encoded combined resource ID without verifying that the server issued it. A forged ID can cause unbounded decoded output, add unique reconstructed IDs to a process-lifetime cache, or combine resources other than stylesheets and scripts. Because jakarta.faces.RESOURCE_EXCLUDES is not applied by this custom resolution path, a forged ID can disclose Facelets source from the webapp resource tree or META-INF/resources. In a deployment configured with the wildcard CDN mapping, a forged ID that selects omnifaces.graphic can also cause a blind, deployment-dependent server-side fetch whose destination derives partly from the request Host header. The flaw does not provide arbitrary file read or establish arbitrary-scheme or arbitrary-destination SSRF. The shared authenticity failure permits memory exhaustion and limited resource disclosure. This issue is fixed in versions 1.14.3, 2.7.33, 3.14.23, 4.7.12, and 5.4.2.

Affected: Maven: org.omnifaces:omnifaces

## 1. Forged combined-resource IDs `CombinedResourceInfo` accepts a path-derived ID without an authenticity check, inflates it without an output limit, converts it to attacker-selected resource identifiers, and retains unique IDs in an unbounded static cache. In bounded tests, 20,754 encoded bytes inflated to 16,000,000 characters (about 770:1; about 49 MB observed heap delta), and 200 unique IDs added 200 permanent cache entries. A legitimately shaped short ID remained about 1:1, while malformed input was rejected; the missing distinction is between a server-issued ID and an attacker-minted but structurally valid ID.

The minimal application also confirmed three sink tails from the same forged-ID root:

- A wildcard CDN mapping performed a server-side fetch and relayed the exact loopback-canary body. This requires the documented combined-resource and wildcard-CDN configuration. - A forged inner `.xhtml` resource bypassed the excluded-resource boundary and returned its raw content. - A forged `omnifaces.graphic` inner resource plus a canary `Host` header caused an outbound GET to that host. This result is blind and deployment-dependent; I am not claiming arbitrary-scheme or arbitrary-destination SSRF.

These behaviors reproduce after the fix for CVE-2026-41883 / GHSA-vp6r-9m58-5xv8. That advisory concerned EL evaluation order in the wildcard CDN path. This report has a different root: unsigned combined IDs and missing decode/cache bounds, with separately demonstrat…