OmniFaces: Forged combined-resource IDs and related output/push boundaries
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:
.xhtml resource bypassed the excluded-resource boundary and
returned its raw content.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.
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.
A URL-fragment value containing a single-quote JavaScript payload was stored by
o:hashParam and later written unescaped into the Ajax callback script. On the
follow-up Ajax render, real Chrome executed the canary
window.__omniXss=1337. This requires a page using o:hashParam and the
follow-up Ajax render.
A fresh WebSocket client with no HTTP cookie connected using a victim's session-scoped channel ID and received the victim's subsequent push. The code checks application-wide ID existence but does not bind the handshake to the current HTTP session, despite the documented current-session guarantee. The UUID remains an unguessable bearer-token prerequisite; this is replay after token exposure, not brute force.
Twelve independent clients joined one application-scoped channel and all 12 received the same push. Current code sets every accepted session's maximum idle timeout to zero, retains sessions in an unbounded per-channel queue, and walks the full queue on each push. I am reporting the demonstrated mechanism as a bounded design weakness: container connection limits remain an outer bound, and I am not claiming unbounded heap growth from the 12-client test.
Servlets.facesRedirect XML issue is fixed on the current branch.
I am not reporting it as a new current-upstream issue.Host header.HashParam values must be escaped for a JavaScript string inside an XML
CDATA callback.Host value.HashParam callback
values.Daniel Birtwhistle
왜 이 VPI인가 (설명가능 · 실험적)
VPI 산정 기준
| 영향도 | 75.00 |
| 악용 신호(추가 악용신호 없음) | ×1.00 |
| VPI | 75.00 |
VPI 공식 vpi-v1 기준