CVE-2025-53645
Zimbra Collaboration (ZCS) before 9.0.0 Patch 46, 10.0.x before 10.0.15, and 10.1.x before 10.1.9 is vulnerable to a denial of service condition due to improper handling of excessive, comma-separated path segments in the Admin Console.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Zimbra Collaboration (ZCS) before 9.0.0 Patch 46, 10.0.x before 10.0.15, and 10.1.x before 10.1.9 is vulnerable to a denial of service condition due to improper handling of excessive, comma-separated path segments in the Admin Console. An unauthenticated remote attacker can send specially crafted GET requests that trigger redundant processing and inflated responses. This leads to uncontrolled resource consumption, resulting in denial of service.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.61% probability · 76th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Source
- cve@mitre.org
EPSS 1.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://wiki.zimbra.com/wiki/Security_Center
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.15#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.9#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P46#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.