zimbra has 8 CVEs on record between 2025 and 2026. Disclosure cadence is accelerating: 7 in the last 90 days against 0 in the 90 before. The busiest recent month was September 2026 with 4. The median CVSS is 8.2 (high), with 4 rated critical. None have a confirmed exploitation report. The most common weakness class is CWE-79 (3). Most affected products: Zimbra Collaboration Suite (ZCS) (4), Zimbra Collaboration Suite (3), collaboration (1).
CVEs per month
Last 12 months, by publish date
- Exploited share
- 0% vs 1% corpus
- Median CVSS
- 8.2
- Publish → KEV
- —
- Last 90 days
- 7 prev 0
Products
- Zimbra Collaboration Suite (ZCS) 4
- Zimbra Collaboration Suite 3
- collaboration 1
Worst active — by depth score
CVE-2026-93643Critical· 9.8When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigned save fields to perform path-traversal writes and execute commands as zimbra.54CVE-2026-93647Critical· 9.3An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address51CVE-2026-93642Critical· 9.3An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.51CVE-2026-93641Critical· 9.3An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Classic recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.51CVE-2026-50055Medium· 6.5A policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send copies of email content and headers to an arbitrary address.48
zimbra vulnerabilities
CVEs affecting zimbra, newest first. Open any entry for full detail, references, and exploit status.
8 CVEsRSS
CVE-2026-10631Medium· 6.5An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary loc…
An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary loc…
CVE-2026-50055Medium· 6.5PoCA policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send copies of email content and headers to an arbitrary address.
A policy-enforcement flaw in Zimbra Collaboration Suite allows an authenticated user to bypass disabled mail forwarding by using a Sieve notify action to send copies of email content and headers to an arbitrary address.
CVE-2026-50054High· 7.1An authorization flaw in Zimbra Collaboration Suite’s GrantRightsRequest allows an attacker with access to an authenticated account to grant another local account the loginAs right, creating persistent mailbox access and mail-sending aut…
An authorization flaw in Zimbra Collaboration Suite’s GrantRightsRequest allows an attacker with access to an authenticated account to grant another local account the loginAs right, creating persistent mailbox access and mail-sending aut…
CVE-2026-93642Critical· 9.3An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Modern recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
CVE-2026-93641Critical· 9.3An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Classic recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
An unauthenticated sender can forge a share notification that triggers stored XSS when a signed-in Zimbra Classic recipient clicks Accept Share, allowing the attacker to access mailbox data and act as the victim.
CVE-2026-93643Critical· 9.8When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigned save fields to perform path-traversal writes and execute commands as zimbra.
When OnlyOffice/Document Editing is available, an unauthenticated remote attacker with access to an existing supported public Briefcase document can abuse unsigned save fields to perform path-traversal writes and execute commands as zimbra.
CVE-2026-93647Critical· 9.3An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address
An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim.
CVE-2025-67809Medium· 4.7An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A hardcoded Flickr API key and secret are present in the publicly accessible Flickr Zimlet used by Zimbra Collaboration. Because these credentials are embedded directly…