An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1.
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Tampering
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-352.
Summary
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A Cross-Site Request Forgery (CSRF) vulnerability exists in Zimbra Web Client due to the issuance of authentication tokens without CSRF protection during certain account state transitions. Specifically, tokens generated after operations such as enabling two-factor authentication or changing a password may lack CSRF enforcement. While such a token is active, authenticated SOAP requests that trigger token generation or state changes can be performed without CSRF validation. An attacker could exploit this by inducing a victim to submit crafted requests, potentially allowing sensitive account actions such as disabling two-factor authentication. The issue is mitigated by ensuring CSRF protection is consistently enforced for all issued authentication tokens.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* | 10.0.0 to before 10.0.18; 10.1.0 to before 10.1.13 | Vulnerable | Synacor |
- cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* Versions 10.0.0 to before 10.0.18; 10.1.0 to before 10.1.13 Vulnerable ·Synacor
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-33373
- 2026-10-03 Alias added: GHSA-pqjp-hqqg-x9w2
- 2026-10-25 Priority changed: MEDIUM → LOW
References
More Synacor Zimbra Collaboration Suite vulnerabilities
- TI-2024-30554 The postjournal service in Zimbra Collaboration (ZCS) before 8.8.15 Patch 46, 9 before… KEVCVSS 3.1CRITICAL 10.0
- TI-2022-19841 An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. KEVCVSS 3.1CRITICAL 9.8
- TI-2022-17239 Zimbra Collaboration Suite (ZCS) 8.8.15 and 9.0 has mboximport functionality that… KEVCVSS 3.1CRITICAL 9.8
- TI-2022-10792 Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to… KEVCVSS 3.1CRITICAL 9.8
- TI-2020-06312 Zimbra Collaboration Suite (ZCS) before 8.8.15 Patch 7 allows SSRF when WebEx zimlet is… KEVCVSS 3.1CRITICAL 9.8
- TI-2019-07076 mailboxd component in Synacor Zimbra Collaboration Suite 8.7.x before 8.7.11p10 has an… KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-33373 · CVE Program
- CVE-2026-33373 · NVD
- FIRST EPSS
- GHSA-pqjp-hqqg-x9w2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences