CVE-2026-50053 (GCVE-0-2026-50053)
Vulnerability from cvelistv5
Published
2026-10-23 13:15
Modified
2026-10-28 20:02
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-642 - External Control of Critical State Data
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.
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Zimbra | Zimbra Collaboration Suite |
Version: 0 ≤ 10.1.17 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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