Vulnerability Description
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 Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openwrt | Openwrt | < 24.10.6 |
Related Weaknesses (CWE)
References
- https://github.com/openwrt/openwrt/releases/tag/v24.10.6Release Notes
- https://github.com/openwrt/openwrt/releases/tag/v25.12.1Release Notes
- https://github.com/openwrt/openwrt/security/advisories/GHSA-mpgh-v658-jqv5Vendor Advisory
FAQ
What is CVE-2026-30872?
CVE-2026-30872 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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_addr...
How severe is CVE-2026-30872?
CVE-2026-30872 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-30872?
Check the references section above for vendor advisories and patch information. Affected products include: Openwrt Openwrt.