CVE-2026-50053 (GCVE-0-2026-50053)

Vulnerability from cvelistv5 – Published: 2026-10-23 13:15 – Updated: 2026-10-23 13:38
VLAI
Title
Zimbra Collaboration Suite RestFilter Request Attribute Override via Unauthenticated URL Parameters
Summary
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.
Severity
8.7 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
CWE
  • CWE-642 - External Control of Critical State Data
Assigner
rapid7 CNA under the mitre root
CNA scorecard B 76/100 over 81 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Zimbra Zimbra Collaboration Suite Affected: 0 , ≤ 10.1.17 (semver)
guessed Create a notification for this product.
Date Public
2026-10-23 12:42
Credits
Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7
Show details on NVD website
To clipboard 

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