Zimbra Collaboration Suite RestFilter Request Attribute Override via Unauthenticated URL Parameters (Zimbra Zimbra Collaboration Suite)

CVE-2026-50053
HIGH 8.7

At a glance

Source
NVD
EPSS
EPSS 0.30 % · percentile 23 ()
State
PUBLISHED
Published
Updated
Assigner
rapid7
NVD status
Undergoing Analysis

Description

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.

Weaknesses (CWE)

  • CWE-642 — External Control of Critical State Data

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.7CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Nrapid7
CVSS 3.1HIGH 8.7CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:NNVD · cve@rapid7.com (Secondary)

European references

Affected products

ProductVersions
Zimbra · Zimbra Collaboration Suiteaffected 0 ≤ 10.1.17

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD