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CVE-2026-73576

Status: AnalyzedMedium (6.5)—

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Synacor — Zimbra Collaboration Suite

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2026-73576",
  "cveTags": [],
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          "version": "2.0.3",
          "timestamp": "2026-08-13T15:49:28.578529Z"
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  "lastModified": "2026-08-28T13:08:02.883",
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