CVE-2026-50056 json
Zimbra Collaboration Suite Local Privilege Escalation via zmmailboxdmgr JVM Argument Injection
published 2026-10-23 17 d ago modified 2026-10-29 11 d ago also EUVD-2026-108979
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
A local privilege escalation vulnerability in the zmmailboxdmgr launcher of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to execute arbitrary commands as root. The passwordless sudo interface accepts JVM arguments that are not adequately restricted. An attacker can postpone Jetty's privilege drop, register an OnOutOfMemoryError command and force heap exhaustion during startup, causing the command to execute while the JVM still runs as root. Exploitation requires local command execution as zimbra on a mailbox server and interrupts mailboxd during the malicious restart. ZCS 10.1.16 and 10.1.21 are affected.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 16 d ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Zimbra Zimbra Collaboration Suite
Classification
- Weakness
-
- CWE-88 Improper Neutralization of Argument Delimiters in a Command
References
Sources
- CVE List CVE-2026-50056
- NVD CVE-2026-50056
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.