CVE-2026-50053

highpriority · track · 0EPSS 0.003 · 23 %ile
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.30% (23rd) EPSS
CVSS 8.7 · high
Is it mine?
0 products
Check your exposure
Who says so?
— sources

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.7
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.7highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Nsecondary · cve@rapid7.comexploitability 2.3 · impact 5.8
v3.18highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-642USCWE-642US
03

affected products

Products and version ranges known to be affected.

No affected products recorded.

04

sources

Which sources assert this record, and when.

NVDCVE.orgMITRE
published 2026-10-23modified 2026-10-23
05

references (2) nvd

External citations — patches, advisories, analysis.

scry

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