Vulnerability · Published Aug 13, 2026 · Assigned by mitre

CVE-2026-73576

Medium 6.3

In plain English

A medium-severity security flaw in Collaboration from Zimbra. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).

Severity (CVSS 3.1)6.3Medium

Exploit odds (30 days)0.3%top 73.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
Zimbra	Collaboration	0 – before 10.1.17

Weakness: CWE-1241 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:N

In plain English

Official description

Affected products (as reported)

References