USN-8997-1: Net-SNMP vulnerability

Published Nov 4, 2026
·
Updated

It was discovered that Net-SNMP incorrectly handled newly accepted connections in the SMUX module. An unauthenticated remote attacker could possibly use this issue to cause Net-SNMP to block indefinitely, resulting in a denial of service.

Affected Software

18 affected componentsFixes available
All of the following
ubuntu/libsnmp40t64<5.9.4+dfsg-2ubuntu3.1
5.9.4+dfsg-2ubuntu3.1
Ubuntu Ubuntu=26.04
All of the following
ubuntu/snmp<5.9.4+dfsg-2ubuntu3.1
5.9.4+dfsg-2ubuntu3.1
Ubuntu Ubuntu=26.04
All of the following
ubuntu/snmpd<5.9.4+dfsg-2ubuntu3.1
5.9.4+dfsg-2ubuntu3.1
Ubuntu Ubuntu=26.04
All of the following
ubuntu/libsnmp40t64<5.9.4+dfsg-1.1ubuntu3.3
5.9.4+dfsg-1.1ubuntu3.3
Ubuntu Ubuntu=24.04
All of the following
ubuntu/snmp<5.9.4+dfsg-1.1ubuntu3.3
5.9.4+dfsg-1.1ubuntu3.3
Ubuntu Ubuntu=24.04
All of the following
ubuntu/snmpd<5.9.4+dfsg-1.1ubuntu3.3
5.9.4+dfsg-1.1ubuntu3.3
Ubuntu Ubuntu=24.04
All of the following
ubuntu/libsnmp40<5.9.1+dfsg-1ubuntu2.10
5.9.1+dfsg-1ubuntu2.10
Ubuntu Ubuntu=22.04
All of the following
ubuntu/snmp<5.9.1+dfsg-1ubuntu2.10
5.9.1+dfsg-1ubuntu2.10
Ubuntu Ubuntu=22.04
All of the following
ubuntu/snmpd<5.9.1+dfsg-1ubuntu2.10
5.9.1+dfsg-1ubuntu2.10
Ubuntu Ubuntu=22.04

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/libsnmp40t64 to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-2ubuntu3.1
  2. Upgrade

    Upgrade ubuntu/snmp to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-2ubuntu3.1
  3. Upgrade

    Upgrade ubuntu/snmpd to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-2ubuntu3.1
  4. Upgrade

    Upgrade ubuntu/libsnmp40t64 to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-1.1ubuntu3.3
  5. Upgrade

    Upgrade ubuntu/snmp to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-1.1ubuntu3.3
  6. Upgrade

    Upgrade ubuntu/snmpd to a version that resolves this vulnerability.

    Fixed in 5.9.4+dfsg-1.1ubuntu3.3
  7. Upgrade

    Upgrade ubuntu/libsnmp40 to a version that resolves this vulnerability.

    Fixed in 5.9.1+dfsg-1ubuntu2.10
  8. Upgrade

    Upgrade ubuntu/snmp to a version that resolves this vulnerability.

    Fixed in 5.9.1+dfsg-1ubuntu2.10
  9. Upgrade

    Upgrade ubuntu/snmpd to a version that resolves this vulnerability.

    Fixed in 5.9.1+dfsg-1ubuntu2.10

Event History

Nov 4, 2026
Advisory Published
via Ubuntu·12:00 AM
Data Sourced
via Ubuntu·12:00 AM
DescriptionAffected Software

Child vulnerabilities

Contains the following vulnerabilities.

Frequently Asked Questions

1

What access does an attacker need to trigger the denial of service?

The issue can be triggered by an unauthenticated remote attacker. The affected component is the SMUX module handling newly accepted connections.

2

What is the impact if the vulnerability is exploited?

Net-SNMP may block indefinitely, causing a denial of service.

Company

Resources

Contact

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