CVE-2026-50053Published

Zimbra Collaboration Suite RestFilter Request Attribute Override via Unauthenticated URL Parameters

Exact source revision recorded 23 Oct 2026 16:01:20 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

cve-program · CVE-2026-50053

Published

A request attribute override vulnerability in Zimbra Collaboration Suite (ZCS) allows unauthenticated requests to /h/* to populate servlet attributes intended for trusted internal dispatch. RestFilter copies URL parameters specifying an authentication token, target account, target item and dispatch state into the request attributes consumed by the Classic Web Client. Combined with CVE-2026-10632 on ZCS 10.1.16, this allows an attacker to supply their own valid token and document identifiers and execute JavaScript in another user's signed-in browser session. ZCS 10.1.17 blocks that XSS chain by changing the document renderer, but retains the request attribute override.

Source published: 23 Oct 2026 13:15:44 UTC
Source modified: 23 Oct 2026 13:38:40 UTC
Observed here: 23 Oct 2026 16:01:20 UTC
Source terms: CVE Program Terms of Use

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 8.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N