--- title: "Zimbra Collaboration Suite (ZCS) vulnerabilities and CVEs" url: https://radicalnotion.ai/vendor/zimbra/zimbra-collaboration-suite-zcs type: product description: "Zimbra Collaboration Suite (ZCS) has 7 published CVEs, 3 in CISA KEV and 3 with public exploits." updated: 2026-09-25 source: RadicalNotion.AI license: CC BY-NC 4.0 (https://creativecommons.org/licenses/by-nc/4.0/) --- # Zimbra Collaboration Suite (ZCS) vulnerabilities Vendor: [Zimbra](https://radicalnotion.ai/vendor/zimbra) - **Published CVEs:** 7 - **In CISA KEV:** 3 - **With a public exploit:** 3 - **With a patch:** 7 - **Average CVSS:** 8.9 - **First CVE:** 2018-03-27 - **Latest CVE:** 2026-09-25 ## Severity breakdown | Severity | CVEs | | --- | --- | | Critical | 6 | | High | 0 | | Medium | 1 | | Low | 0 | | Unscored | 0 | ## Most common weakness types | CWE | Name | CVEs | | --- | --- | --- | | [CWE-79](https://radicalnotion.ai/cwe/cwe-79) | Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') | 4 | | [CWE-22](https://radicalnotion.ai/cwe/cwe-22) | Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') | 1 | | [CWE-78](https://radicalnotion.ai/cwe/cwe-78) | Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') | 1 | | [CWE-918](https://radicalnotion.ai/cwe/cwe-918) | Server-Side Request Forgery (SSRF) | 1 | ## CVEs by year | Year | CVEs published | | --- | --- | | 2018 | 1 | | 2019 | 0 | | 2020 | 1 | | 2021 | 0 | | 2022 | 0 | | 2023 | 0 | | 2024 | 1 | | 2025 | 0 | | 2026 | 4 | ## Affected versions | Version | Kind | CVEs | | --- | --- | --- | | \< 10.1.21 | range | 4 | | 10.1.21 | patched | 4 | ## CVEs | CVE | Title | Severity | CVSS | CISA KEV | Public exploit | Patch | | --- | --- | --- | --- | --- | --- | --- | | CVE-2026-93647 | Zimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Crafted Calendar COUNTER Message From Address | critical | 9.3 | No | No | Yes | | CVE-2026-93643 | Zimbra Collaboration Suite OnlyOffice Integration Path Traversal Leading to Remote Code Execution via Unauthenticated /downloadas Request | critical | 9.8 | No | No | Yes | | CVE-2026-93642 | Zimbra Collaboration Suite Modern Web Client Stored Cross-Site Scripting via Forged Share Invitation | critical | 9.3 | No | No | Yes | | CVE-2026-93641 | Zimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Forged Share Invitation | critical | 9.3 | No | No | Yes | | CVE-2024-45519 | - | critical | 9.3 | Yes | Yes | Yes | | CVE-2020-7796 | - | critical | 9.3 | Yes | Yes | Yes | | CVE-2018-6882 | - | medium | 6.3 | Yes | Yes | Yes | ## Frequently asked questions ### How many CVEs does Zimbra Collaboration Suite (ZCS) have? Zimbra Collaboration Suite (ZCS) has 7 published CVE records since 2018. ### How many Zimbra Collaboration Suite (ZCS) CVEs are in CISA KEV? 3 of Zimbra Collaboration Suite (ZCS)'s CVEs are listed in CISA's Known Exploited Vulnerabilities catalog, confirmed exploited in the wild and carrying a CISA remediation deadline. ### Are there public exploits for Zimbra Collaboration Suite (ZCS) vulnerabilities? Yes — 3 of Zimbra Collaboration Suite (ZCS)'s CVEs have a known public exploit. ### Which versions of Zimbra Collaboration Suite (ZCS) are affected? 2 distinct Zimbra Collaboration Suite (ZCS) versions are named across its CVEs. Use the version filter above to see the CVEs affecting a specific version. ### What are the most common weakness types in Zimbra Collaboration Suite (ZCS) CVEs? Zimbra Collaboration Suite (ZCS)'s CVEs most often map to these CWE weakness types: CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')), CWE-22 (Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')), CWE-78 (Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')), CWE-918 (Server-Side Request Forgery (SSRF)). ### How many critical Zimbra Collaboration Suite (ZCS) vulnerabilities are there? Zimbra Collaboration Suite (ZCS) has 6 critical and 0 high-severity CVEs. ### What is the average severity of Zimbra Collaboration Suite (ZCS) CVEs? The average CVSS base score across Zimbra Collaboration Suite (ZCS)'s scored CVEs is 8.9. ## Other products from this vendor - [zm-build](https://radicalnotion.ai/vendor/zimbra/zm-build) (114 CVEs) - [Collaboration](https://radicalnotion.ai/vendor/zimbra/collaboration) (50 CVEs) - [Zimbra Collaboration Suite](https://radicalnotion.ai/vendor/zimbra/zimbra-collaboration-suite) (25 CVEs) - [zm-mailbox](https://radicalnotion.ai/vendor/zimbra/zm-mailbox) (19 CVEs) - [zm-zcs-lib](https://radicalnotion.ai/vendor/zimbra/zm-zcs-lib) (12 CVEs) - [zm-zcs](https://radicalnotion.ai/vendor/zimbra/zm-zcs) (11 CVEs) - [collaboration server](https://radicalnotion.ai/vendor/zimbra/collaboration-server) (6 CVEs) - [Zimbra](https://radicalnotion.ai/vendor/zimbra/zimbra) (5 CVEs) --- Source: [RadicalNotion.AI](https://radicalnotion.ai/vendor/zimbra/zimbra-collaboration-suite-zcs). Licensed CC BY-NC 4.0; attribute RadicalNotion.AI and link the source page when you reuse this data.