Vulnerability-Lookup

UBUNTU-CVE-2026-104733 (CVE-2026-104733)

Vulnerability from osv_ubuntu – Published: 2026-10-02 13:17 – Updated: 2026-10-08 09:54 – Source website

Details

User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an attacker to impersonate arbitrary users via unvalidated authzid parameter in SASL-PLAIN mechanism.

Severity

7.4 (High)


                    
                      CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:H/SI:H/SA:H/E:P

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-104733	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-104733	REPORT
	https://www.nsideattacklogic.de/advisories/NSIDE-…	REPORT
	https://github.com/processone/ejabberd/releases#r…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "16.01-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@16.01-2?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "15.03-2",
        "15.10-3",
        "16.01-1",
        "16.01-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "18.01-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@18.01-2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "17.07-1",
        "17.08-3",
        "17.11-1",
        "18.01-1",
        "18.01-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "20.01-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@20.01-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "19.08-2",
        "19.09.1-1",
        "20.01-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "21.12-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@21.12-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "21.01-2",
        "21.07-1",
        "21.12-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "23.10-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@23.10-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "23.01-1",
        "23.10-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ejabberd",
            "binary_version": "24.12-4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "ejabberd",
        "purl": "pkg:deb/ubuntu/ejabberd@24.12-4?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "24.12-3",
        "24.12-4"
      ]
    }
  ],
  "aliases": [],
  "details": "User Impersonation in ProcessOnes XMMP Server ejabberd \u003c= 26.04 allows an attacker to impersonate arbitrary users via unvalidated authzid parameter in SASL-PLAIN mechanism.",
  "id": "UBUNTU-CVE-2026-104733",
  "modified": "2026-10-08T09:54:47Z",
  "published": "2026-10-02T13:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-104733"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-104733"
    },
    {
      "type": "REPORT",
      "url": "https://www.nsideattacklogic.de/advisories/NSIDE-SA-2026-004/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/processone/ejabberd/releases#release-26.07"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:H/SI:H/SA:H/E:P",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-104733"
  ]
}

CVE-2026-104733 (GCVE-0-2026-104733)

Vulnerability from cvelistv5 – Published: 2026-10-02 12:19 – Updated: 2026-10-02 16:57

Title

User Impersonation/Authorization Bypass in XMPP Server ejabberd

Summary

User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an attacker to impersonate arbitrary users via unvalidated authzid parameter in SASL-PLAIN mechanism.

Severity

7.4 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:H/SI:H/SA:H/E:P

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-02 16:56 UTC

CWE

User Impersonation
CWE-290 - Authentication Bypass by Spoofing

Assigner

NCSC.ch mitre root Scorecard

References

2 references

URL	Tags
https://www.nsideattacklogic.de/advisories/NSIDE-…	third-party-advisory
https://github.com/processone/ejabberd/releases#r…	release-notes

Impacted products

1 product

Vendor	Product	Version
ProcessOne	ejabberd	Affected: 0 , ≤ 26.04 (custom)

Date Public

2026-07-31 09:01

Credits

Marius Schwarz (NSIDE ATTACK LOGIC GmbH)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
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        "metrics": [
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                "id": "CVE-2026-104733",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-02T16:56:58.717189Z",
                "version": "2.0.3"
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            }
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                "description": "CWE-290 Authentication Bypass by Spoofing",
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        "providerMetadata": {
          "dateUpdated": "2026-10-02T16:57:18.308Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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            "Recovery": "NOT_DEFINED",
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            "attackVector": "NETWORK",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
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            "subConfidentialityImpact": "HIGH",
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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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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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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UBUNTU-CVE-2026-104733 (CVE-2026-104733)

CVE-2026-104733 (GCVE-0-2026-104733)

Tags

Sightings

Nomenclature

Related by attack behaviour