{"id":"CVE-2026-73576","title":"In Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation vulnerability exists in the OnlyOffice integration","summary":"In Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation vulnerability exists in the OnlyOffice integration. The zimbraDocumentEditingJwtSecret is generated using an insecure random number generator, resulting in i…","severity":"medium","cvss":6.3,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:N","cwe":["CWE-1241"],"published":"2026-08-13","updated":"2026-08-21","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-73576","references":[{"url":"https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy","label":"cve@mitre.org"},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories","label":"cve@mitre.org"}],"tags":["nvd"],"epss":0.00194,"epssPercentile":0.09347,"ingestedAt":"2026-08-22T13:32:36.305Z","slug":"CVE-2026-73576","body":"## Overview\n\nIn Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation vulnerability exists in the OnlyOffice integration. The zimbraDocumentEditingJwtSecret is generated using an insecure random number generator, resulting in insufficient entropy. An attacker who obtains a JWT signed with the generated secret may be able to recover the JWT signing secret through offline brute-force, potentially enabling JWT forgery.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":35,"depthScoreParts":{"impact":34.7,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}