CVE-2021-3448

MEDIUM
Published Apr 8, 20215y ago · Modified Jun 17, 20262w ago
4.0 CVSS 3.1
Medium
Find Similar
Published Apr 8, 2021 5y ago
Last Modified Jun 17, 2026 2w ago

Description

A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.

CVSS Details

Base Score
4.0
Exploitability
2.2
Impact
1.4
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Changed
Confidentiality None
Integrity Low
Availability None

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-358

Affected Products 6

VendorProductVersionRange
thekelleysdnsmasq* <2.85
redhatenterprise_linux8.0any
fedoraprojectfedora32any
fedoraprojectfedora33any
fedoraprojectfedora34any
oraclecommunications_cloud_native_core_network_function_cloud_native_environment1.9.0any

References 6

  • bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=1939368
    ExploitIssue TrackingPatchThird Party Advisory
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/
  • security.gentoo.org https://security.gentoo.org/glsa/202105-20
    Third Party Advisory
  • oracle.com https://www.oracle.com/security-alerts/cpujan2022.html
    PatchThird Party Advisory

Remediation

  • bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=1939368
    ExploitIssue TrackingPatchThird Party Advisory
  • oracle.com https://www.oracle.com/security-alerts/cpujan2022.html
    PatchThird Party Advisory