CVE-2026-93631 (GCVE-0-2026-93631)

Vulnerability from cvelistv5 – Published: 2026-10-23 13:23 – Updated: 2026-10-23 13:23
VLAI
Title
Zimbra Collaboration Suite OAuth Extension Cross-Site Request Forgery Enables Account Linking
Summary
A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
CWE
  • CWE-352 - Cross-Site request forgery (CSRF)
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 , ≤ 10.1.20 (semver)
guessed Create a notification for this product.
Date Public
2026-10-23 12:51
Credits
Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7
Show details on NVD website
To clipboard 

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