CVE-2026-93631Zimbra Collaboration Suite OAuth Extension Cross-Site Request Forgery Enables Account Linking
Updated under an hour ago ()
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It affects Zimbra Collaboration Suite. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.14%, higher than 4% of scored CVEs.
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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.
- CVSS
- 7.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
- Weakness (CWE)
- CWE-352
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.14% (percentile 4)
- Assigned by
- rapid7
- NVD analysis
- Awaiting Analysis
- Record last updated
- Oct 23, 2026
- First seen by InfoSec Signals
- Oct 23, 2026
The CVE record on cve.org NVD's entry
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