CVE-2026-89147 (GCVE-0-2026-89147)
Vulnerability from cvelistv5 – Published: 2026-09-11 10:46 – Updated: 2026-09-11 10:46
VLAI
EPSS
VEX
Title
Net-SNMP through 5.9.5.2 Denial of Service via Blocking Unauthenticated SMUX Read
Summary
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.
Severity
CWE
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://gist.github.com/thesmartshadow/001cea595e… | third-party-advisory |
| https://github.com/net-snmp/net-snmp/blob/v5.9.5.… | technical-description |
| https://github.com/net-snmp/net-snmp | product |
| https://www.vulncheck.com/advisories/net-snmp-thr… | third-party-advisory |
Impacted products
Date Public
2026-09-09 00:00
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"packageURL": "pkg:github/net-snmp/net-snmp",
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"vendor": "net-snmp",
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"providerMetadata": {
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"source": {
"discovery": "UNKNOWN"
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"title": "Net-SNMP through 5.9.5.2 Denial of Service via Blocking Unauthenticated SMUX Read",
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"dateReserved": "2026-09-11T01:23:34.216Z",
"dateUpdated": "2026-09-11T10:46:56.944Z",
"state": "PUBLISHED"
},
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"dataVersion": "5.2",
"vulnerability-lookup:meta": {
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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