CVE-2026-30872

OpenWrt Project is a Linux operating system targeting embedded devices. In versions prior to 24.10.6 and 25.12.1, the mdns daemon has a Stack-based Buffer Overflow vulnerability in the match_ipv6_addresses function, triggered when processing PTR queries for IPv6 reverse DNS domains (.ip6.arpa) received via multicast DNS on UDP port 5353. During processing, the domain name from name_buffer is copied via strcpy into a fixed 256-byte stack buffer, and then the reverse IPv6 request is extracted into a buffer of only 46 bytes (INET6_ADDRSTRLEN). Because the length of the data is never validated before this extraction, an attacker can supply input larger than 46 bytes, causing an out-of-bounds write. This allows a specially crafted DNS query to overflow the stack buffer in match_ipv6_addresses, potentially enabling remote code execution. This issue has been fixed in versions 24.10.6 and 25.12.1.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/openwrt/openwrt/releases/tag/v24.10.6	Release Notes
https://github.com/openwrt/openwrt/releases/tag/v25.12.1	Release Notes
https://github.com/openwrt/openwrt/security/advisories/GHSA-mpgh-v658-jqv5	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:openwrt:openwrt::::::::
	cpe:2.3:o:openwrt:openwrt::::::::

History

No history.

Information

Published : 2026-03-19 22:16

Updated : 2026-03-24 14:05

NVD link : CVE-2026-30872

Mitre link : CVE-2026-30872

CVE.ORG link : CVE-2026-30872

JSON object : View

Products Affected

openwrt

openwrt

CWE

CWE-121

Stack-based Buffer Overflow

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