Skip to main content

dnsmasq EUVDEUVD-2026-38449

| CVE-2026-12969 MEDIUM
Out-of-bounds Read (CWE-125)
2026-06-23 redhat GHSA-wmwj-946w-3m8w
Buffer Overflow Information Disclosure Red Hat Enterprise Linux 10 Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 9 Red Hat Openshift Container Platform 4 Red Hat
5.3
CVSS 3.1 · Vendor: redhat
Share

Severity by source

Vendor (redhat) PRIMARY
5.3 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
vuln.today AI
5.3 MEDIUM

Network delivery via DNS response, no victim-side auth needed, only low confidentiality impact from bounded heap read; no integrity or availability effect described.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
SUSE
6.5 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Red Hat
5.3 LOW
qualitative

Primary rating from Vendor (redhat).

CVSS VectorVendor: redhat

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

Lifecycle Timeline

2
Analysis Generated
Jun 23, 2026 - 14:16 vuln.today
CVE Published
Jun 23, 2026 - 13:28 cve.org
MEDIUM 5.3

DescriptionCVE.org

An out-of-bounds read vulnerability exists in dnsmasq's find_soa() function in src/rfc1035.c. When parsing NS section records, extract_name() is called with extrabytes=0, failing to validate that 10 additional bytes exist for fixed-length DNS record fields. A remote attacker controlling a DNS zone can exploit this via a crafted NXDOMAIN response to cause a 10-byte heap out-of-bounds read, potentially accessing stale data from prior transactions.

AnalysisAI

Heap out-of-bounds read in dnsmasq's find_soa() function allows a remote attacker controlling a DNS zone to leak up to 10 bytes of stale heap memory by serving a crafted NXDOMAIN response. The flaw exists because extract_name() is invoked with extrabytes=0 when parsing NS section records, skipping the mandatory boundary check for the 10-byte fixed-length DNS record trailer fields. Confirmed affected platforms include Red Hat Enterprise Linux 6 through 10 and OpenShift Container Platform 4; no public exploit or CISA KEV listing has been identified at time of analysis.

Technical ContextAI

dnsmasq is a lightweight DNS forwarder and DHCP server widely shipped in Linux distributions and container environments. The vulnerable code path is in src/rfc1035.c within find_soa(), which processes DNS NS (Name Server) resource records returned in NXDOMAIN responses. The function calls extract_name() with extrabytes=0, meaning it does not reserve space for the 10 bytes that follow the domain name in a standard DNS RR: 2 bytes TYPE + 2 bytes CLASS + 4 bytes TTL + 2 bytes RDLENGTH. When a crafted response places the NS record near the end of the DNS message buffer, the subsequent field access reads 10 bytes past the validated boundary - a classic CWE-125 (Out-of-Bounds Read) on the heap. Affected CPEs span cpe:2.3:a:red_hat:red_hat_enterprise_linux_6 through _10 and cpe:2.3:a:red_hat:red_hat_openshift_container_platform_4, indicating Red Hat packages are confirmed affected. The upstream dnsmasq project itself is implicitly affected given the location of the bug in core RFC 1035 parsing logic.

RemediationAI

Monitor the Red Hat security advisory at https://access.redhat.com/security/cve/CVE-2026-12969 and apply the updated dnsmasq package for your RHEL or OpenShift release as soon as it becomes available; no specific fixed version number has been confirmed from the provided data at time of analysis. As a compensating control, restrict the DNS zones that dnsmasq forwards queries to by limiting upstream resolvers to trusted, internal servers rather than arbitrary public zones - this reduces attacker ability to control NXDOMAIN responses seen by the resolver. If dnsmasq is used solely for DHCP with DNS forwarding disabled (--port=0), the vulnerable code path in find_soa() is not reachable, eliminating exposure at the cost of DNS functionality. Placing dnsmasq behind a DNS proxy or firewall rule that drops responses from unauthorized name servers provides additional depth. Upgrading to an upstream dnsmasq release that includes the fix, once confirmed via the dnsmasq changelog or upstream repository, is the definitive remediation.

More in Red Hat Enterprise Linux 10

View all
CVE-2026-18663 MEDIUM
5.9 Aug 12

Heap corruption via double-free in 389-ds-base's LDAP control parsing allows an unauthenticated remote attacker to crash
CVE-2026-4631 CRITICAL POC
9.8 Apr 07

Remote code execution in Cockpit's web interface allows unauthenticated attackers to execute arbitrary commands on the h
CVE-2026-4480 CRITICAL POC
9.0 May 26

Remote code execution in Samba's printing subsystem allows remote attackers to inject arbitrary shell commands via craft
CVE-2026-18922 CRITICAL
9.8 Sep 07

Authentication bypass in 389 Directory Server (shipped as Red Hat Directory Server 11-13 and within RHEL 6-10) lets remo
CVE-2026-14544 CRITICAL
9.8 Jul 03

Remote code execution and privilege escalation in HPLIP (HP Linux Imaging and Printing) affects the hpcups print filter

CVE-2026-76578 CRITICAL
9.8 Sep 07

Unauthenticated privilege escalation in FreeIPA (Red Hat Identity Management) allows a remote attacker to gain genuine a
CVE-2026-5121 HIGH
7.5 Mar 30

Remote code execution in libarchive on 32-bit systems allows unauthenticated attackers to execute arbitrary code via spe
CVE-2026-28369 CRITICAL
9.1 Mar 27

HTTP request smuggling in Undertow (the embedded web server underpinning JBoss EAP, Red Hat Data Grid, and Apache Camel

CVE-2026-28368 CRITICAL
9.1 Mar 27

HTTP request smuggling in Red Hat Undertow allows remote unauthenticated attackers to bypass front-end security controls
CVE-2026-33845 CRITICAL
9.1 Apr 30

Out-of-bounds read in the GnuTLS DTLS handshake reassembly logic lets remote unauthenticated attackers trigger an intege
CVE-2026-28367 CRITICAL
9.1 Mar 27

HTTP request smuggling in Undertow allows remote unauthenticated attackers to send `\r\r\r` as a header block terminator
CVE-2026-16526 HIGH
8.8 Jul 30

Local privilege escalation in Performance Co-Pilot (PCP) on Red Hat Enterprise Linux 6 through 10 and OpenShift Containe

Same weakness CWE-125 – Out-of-bounds Read

View all
CVE-2014-0160 HIGH POC
7.5
CVE-2016-5198 HIGH POC
8.8
CVE-2025-5777 CRITICAL POC
9.3
CVE-2016-1646 HIGH POC
8.8
CVE-2017-5030 HIGH POC
8.8
CVE-2016-4523 HIGH
7.5
CVE-2024-48456 HIGH POC
7.5
CVE-2024-48457 HIGH POC
7.5

Same technique Buffer Overflow

View all
CVE-2017-7269 CRITICAL POC
9.8
CVE-2015-5119 CRITICAL POC
9.8
CVE-2015-3113 CRITICAL POC
9.8
CVE-2011-2462 CRITICAL POC
9.8
CVE-2020-0796 CRITICAL POC
10.0
CVE-2019-11043 CRITICAL POC
9.8
CVE-2009-0927 HIGH POC
8.8
CVE-2012-1889 HIGH POC
8.8

Vendor StatusVendor

SUSE

Severity: Moderate
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Affected
SUSE Linux Enterprise High Performance Computing 15 SP7 Affected
SUSE Linux Enterprise Micro 5.3 Affected
SUSE Linux Enterprise Micro 5.4 Affected
SUSE Linux Enterprise Micro 5.5 Affected

Share

EUVD-2026-38449 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy