GHSA-fp43-vj7g-pg92

Details

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 demonstrated residual sink behavior.

2. Source-map cache

With the documented optional source-map handler above a synthetic resource handler, 40 unique missing combined-resource requests grew the process-wide source-map cache from 13 to 92 entries. It has no size or eviction bound. This has a separate cache, configuration prerequisite, and fix from family 1.