CVE-2026-22321 - Vulnerability Details - OpenCVE

A stack-based buffer overflow in the device's Telnet/SSH CLI login routine occurs when a unauthenticated attacker send an oversized or unexpected username input. An overflow condition crashes the thread handling the login attempt, forcing the session to close. Because other CLI sessions remain unaffected, the impact is limited to a low‑severity availability disruption.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00036.

Key SSVC decision points have not yet been added.

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References

Link	Providers
https://certvde.com/de/advisories/VDE-2025-104

History

Wed, 18 Mar 2026 07:45:00 +0000

Type	Values Removed	Values Added
Description		A stack-based buffer overflow in the device's Telnet/SSH CLI login routine occurs when a unauthenticated attacker send an oversized or unexpected username input. An overflow condition crashes the thread handling the login attempt, forcing the session to close. Because other CLI sessions remain unaffected, the impact is limited to a low‑severity availability disruption.
Title		Stack-Based Buffer Overflow in CLI Login Username Handling over CLI
Weaknesses		CWE-121
References		https://certvde.com/de/advisories/VDE-2025-104
Metrics		cvssV3_1 `{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}`

MITRE

Status: PUBLISHED

Assigner: CERTVDE

Published: 2026-03-18T07:34:36.289Z

Updated: 2026-03-18T13:32:24.892Z

Reserved: 2026-01-07T11:49:15.178Z

Link: CVE-2026-22321

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-03-18T08:16:29.527

Modified: 2026-03-18T08:16:29.527

Link: CVE-2026-22321

Redhat

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OpenCVE Enrichment

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