CVE-2026-89147 (GCVE-0-2026-89147)

Vulnerability from cvelistv5 – Published: 2026-09-11 10:46 – Updated: 2026-09-15 16:08
VLAI
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 16:06 UTC
CWE
  • CWE-1088 - Synchronous Access of Remote Resource without Timeout
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
net-snmp Net-SNMP Affected: 0 , ≤ 5.9.5.2 (custom)
    cpe:2.3:a:net-snmp:net-snmp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-09 00:00
Credits
Ali Firas
Show details on NVD website
To clipboard 

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