CVE-2026-120596
📛 CVE Title
CVE-2026-120596
Description
A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- certcc
- CVSS severity
- —
- CVSS score
- —
- CVSS vector
- —
- Effective score
- no score available from CNA, NVD, or AI yet
- CWE(s)
-
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop'),CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer,CWE-20 Improper Input Validation - Reserved
- 2026-11-02
- Published
- 2026-11-02 17:04 UTC
- Last updated
- 2026-11-02 17:17 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/120xxx/CVE-2026-120596.json
AI-forensic CVSS estimate
Used only when a CVE has no official CVSS from its CNA or NVD. An LLM estimates the v3.1 base score from the description; a HIGH/CRITICAL estimate promotes the CVE to a Threat.
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European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-115333
EUVD enrichment is queued; refresh the page in a few seconds.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Ethernut / egnite GmbH | Nut/Net TCP/IP Stack |
Nut/OS 5.1 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
Remediations (10)
-
web:blogs.oracle.com
For more information about the Critical Security Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-11-03 12:34 UTC -
web:sec.cloudapps.cisco.com
As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. These vulnerabilities were found during internal testing and are not known to be actively exploited. To assist customers in patching ...
2026-11-03 12:34 UTC -
web:support.microsoft.com
Summary This security update resolves a Microsoft Word security feature bypass vulnerability. To learn more about the vulnerability, see Microsoft Common Vulnerabilities and Exposures CVE - 2026 -21509.
2026-11-03 12:34 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the Support Portal and applies patches on priority to protect their SAP landscape. On 10th of February 2026 , SAP security patch day saw the release of 26 new security notes. Further, there was 1 update to ...
2026-11-03 12:34 UTC -
web:techcommunity.microsoft.com
Learn more: Azure WAF custom rules for PHP2Shell mitigation . Request-side signals alone may not be sufficient to reliably identify certain exploitation attempts. Signals in the server response can provide additional evidence that malicious activity has occurred, enabling more targeted mitigation with higher confidence and lower false positives.
2026-11-03 12:34 UTC -
web:www.beyondtrust.com
Mitigation As of Oct 9, 2026 , a patch that remediates this vulnerability has been applied to all Remote Support SaaS customers. Self-hosted customers of Remote Support should manually apply the patch if their instance is not subscribed to automatic updates in their / appliance interface.
2026-11-03 12:34 UTC -
web:www.microsoft.com
If you can't patch immediately: Apply the PHP project's interim mitigations and the Azure WAF protections. Note: This reduces exposure but doesn't fix the underlying vulnerabilities.
2026-11-03 12:34 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-11-03 12:34 UTC -
web:www.oracle.com
Prior Critical Patch Update and Critical Security Patch Update advisories should be reviewed for information regarding earlier published security patches. Refer to Critical Patch Updates, Critical Security Patch Updates, Security Alerts and Bulletins for information about Oracle Security advisories.
2026-11-03 12:34 UTC -
web:www.thehackerwire.com
To protect against CVE-2026-120596 , you should: (1) Apply the latest security patches from the vendor, (2) Check official security advisories for specific remediation steps, (3) Update affected software to the latest version, and (4) Monitor your systems for any signs of exploitation. When was CVE-2026-120596 disclosed?
2026-11-03 12:34 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-120596.json.
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