Vulnerability-Lookup

GHSA-WW99-8662-82Q8

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-23 15:31

Details

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.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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  "affected": [],
  "aliases": [
    "CVE-2026-50056"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-88"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T14:17:53Z",
    "severity": "HIGH"
  },
  "details": "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\u0027s 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.",
  "id": "GHSA-ww99-8662-82q8",
  "modified": "2026-10-23T15:31:38Z",
  "published": "2026-10-23T15:31:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50056"
    },
    {
      "type": "WEB",
      "url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories"
    },
    {
      "type": "WEB",
      "url": "https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1"
    }
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  "schema_version": "1.4.0",
  "severity": [
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      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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}

CVE-2026-50056 (GCVE-0-2026-50056)

Vulnerability from cvelistv5 – Published: 2026-10-23 13:30 – Updated: 2026-10-24 03:55

Title

Zimbra Collaboration Suite Local Privilege Escalation via zmmailboxdmgr JVM Argument Injection

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-23 00:00 UTC

CWE

CWE-88 - Improper neutralization of argument delimiters in a command ('argument injection')

Assigner

rapid7 CNA under the mitre root

CNA scorecard B 76/100 over 81 records in the last 180 days details

References

2 references

URL	Tags
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories	vendor-advisory
https://www.rapid7.com/blog/post/ve-breaking-zimb…	related

Impacted products

1 product

Vendor	Product	Version
Zimbra	Zimbra Collaboration Suite	Affected: 0 , ≤ 10.1.21 (semver)

Date Public

2026-10-23 13:05

Credits

Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7

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JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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