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Public proof of conceptFix available

CVE-2018-18066

A public proof of concept exists; no exploitation attested.

  • Published2018-10-08
  • Fixed in5.8
  • WeaknessCWE-476

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

snmp_oid_compare in snmplib/snmp_api.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an unauthenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.

Timeline

dates in UTC
  1. 2018-10-0818:29CVE publishedNVD

Versions per branch

NVD
Net-snmp
BranchAffectedFixed in
5.8< 5.85.8
Netapp cloud backup
BranchAffectedFixed in
—all versionsno fix published
Netapp data ontap
BranchAffectedFixed in
—all versionsno fix published

4 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • net-snmpRed Hat:rhel_eus:7.7::serverall versions · fixed in 1:5.7.2-43.el7_7.6and 9 other packages
  • net-snmpRed Hat:rhel_eus:7.7::computenodeall versions · fixed in 1:5.7.2-43.el7_7.6and 9 other packages
  • net-snmpRed Hat:enterprise_linux:7::workstationall versions · fixed in 1:5.7.2-47.el7and 9 other packages
  • net-snmpRed Hat:enterprise_linux:7::serverall versions · fixed in 1:5.7.2-47.el7and 9 other packages
  • net-snmpRed Hat:enterprise_linux:7::computenodeall versions · fixed in 1:5.7.2-47.el7and 9 other packages
  • net-snmpRed Hat:enterprise_linux:7::clientall versions · fixed in 1:5.7.2-47.el7and 9 other packages
  • net-snmpDebian:14all versions · fixed in 5.7.3+dfsg-1.1
  • net-snmpDebian:13all versions · fixed in 5.7.3+dfsg-1.1

1 more package range on OSV.dev

Vendor advisories

  • CVE-2018-18066 Red Hat Product Security181 products fixed · 7 known affected

    net-snmp: NULL pointer exception in snmp_oid_compare in snmplib/snmp_api.c resulting in a denial of service

    net-snmp as a component of Red Hat Enterprise Linux 6 · net-snmp-devel as a component of Red Hat Enterprise Linux 6 · net-snmp-libs as a component of Red Hat Enterprise Linux 6 · +4 more

  • ICSA-23-234-01 CISA1 known affected

    Hitachi Energy AFF66x

    AFF660/665: <= 03.0.02

  • RHSA-2020:2539 Red Hat Product Security74 products fixed

    Red Hat Security Advisory: net-snmp security and bug fix update

  • RHSA-2020:1081 Red Hat Product Security107 products fixed

    Red Hat Security Advisory: net-snmp security and bug fix update

Full record on NVD

Fix

  1. Update Net-snmp to 5.8
  2. Vendor fix CISA ICSA-23-234-01 · 1 productUpdate to upcoming AFF660/665 FW 04.6.01 release when available.
  3. Vendor fix Red Hat Product Security RHSA-2020:2539 · 74 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  4. Workaround from the vendor Red Hat Product Security RHSA-2020:2539 · 74 productsConfiguring snmp with a secret community string makes this attack much more difficult to perform, as the attacker must guess the community string in order to exploit the vulnerability. Protecting the snmp service with host firewall rules to prevent unauthorized hosts from sending messages to the s…
  5. Mitigation from the vendor CISA ICSA-23-234-01 · 1 productHitachi Energy recommends the following actions:
  6. Mitigation from the vendor CISA ICSA-23-234-01 · 1 productConfigure only trusted DNS server(s).
  7. Mitigation from the vendor CISA ICSA-23-234-01 · 1 productConfigure the NTP service with redundant trustworthy sources of time.

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2018-10-08
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-9mpr-24m6-767p

Frequently asked questions

What is CVE-2018-18066?

snmp_oid_compare in snmplib/snmp_api.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an unauthenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.

Is CVE-2018-18066 actively exploited?

A proof-of-concept exploit exists for CVE-2018-18066, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2018-18066?

CVE-2018-18066 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record