Net-SNMP up to 5.9.5.2 SMUX module smux_accept denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$0-$5k0.00+

Summaryinfo

A vulnerability described as critical has been identified in Net-SNMP up to 5.9.5.2. This impacts the function smux_accept of the component SMUX module. Executing a manipulation can lead to denial of service. This vulnerability is registered as CVE-2026-89147. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in Net-SNMP up to 5.9.5.2. This vulnerability affects the function smux_accept of the component SMUX module. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

Net-SNMP through 5.9.5.2 contains a denial of service vulnerability in the SMUX module where smux_accept() performs an unauthenticated blocking read without timeout on newly accepted connections. An unauthenticated remote client can connect to the SMUX listener and send no data, causing the single-threaded snmpd main loop to block indefinitely and suspend all SNMP processing.

The advisory is shared for download at gist.github.com. This vulnerability was named CVE-2026-89147 since 09/11/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/11/2026). The MITRE ATT&CK project declares the attack technique as T1499.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/11/2026 Advisory disclosed
09/11/2026 +0 days CVE reserved
09/11/2026 +0 days VulDB entry created
09/11/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: gist.github.com
Status: Not defined

CVE: CVE-2026-89147 (🔒)
GCVE (CVE): GCVE-0-2026-89147
GCVE (VulDB): GCVE-100-402400

Entryinfo

Created: 09/11/2026 13:14
Changes: 09/11/2026 13:14 (75)
Complete: 🔍
Cache ID: 216::103

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