Zimbra Collaboration up to 10.1.16 OnlyOffice Integration zimbraDocumentEditingJwtSecret entropy

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Zimbra Collaboration up to 10.1.16. This impacts an unknown function of the component OnlyOffice Integration. Performing a manipulation of the argument zimbraDocumentEditingJwtSecret results in entropy. This vulnerability is reported as CVE-2026-73576. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Zimbra Collaboration up to 10.1.16. It has been classified as problematic. This affects an unknown functionality of the component OnlyOffice Integration. The manipulation of the argument zimbraDocumentEditingJwtSecret with an unknown input leads to a entropy vulnerability. CWE is classifying the issue as CWE-331. The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others. This is going to have an impact on confidentiality. The summary by CVE is:

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 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.

It is possible to read the advisory at wiki.zimbra.com. This vulnerability is uniquely identified as CVE-2026-73576 since 08/13/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1600.001 according to MITRE ATT&CK.

Upgrading to version 10.1.17 eliminates this vulnerability.

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Productinfo

Type

• Groupware Software

Vendor

• Zimbra

Name

• Collaboration

Version

• 10.1.0
• 10.1.1
• 10.1.2
• 10.1.3
• 10.1.4
• 10.1.5
• 10.1.6
• 10.1.7
• 10.1.8
• 10.1.9
• 10.1.10
• 10.1.11
• 10.1.12
• 10.1.13
• 10.1.14
• 10.1.15
• 10.1.16

CPE 2.3info

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CPE 2.2info

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