Is there a public exploit for CVE-2026-30871?

No public exploit for CVE-2026-30871 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-30871?

CVE-2026-30871 scores CVSS 9.5 (v4.0), rated critical. EPSS puts the chance of exploitation in the next 30 days at 1.26%.

What does CVE-2026-30871 affect?

CVE-2026-30871 affects OpenWRT OpenWRT.

9.5 Critical

OpenWrt Project is a Linux operating system targeting embedded devices.

CVE-2026-30871

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 parsequestion function. The issue is triggered by PTR queries for reverse DNS domains (.in-addr.arpa and .ip6.arpa). DNS packets received on UDP port 5353 are expanded by dnexpand into an 8096-byte global buffer (namebuffer), which is then copied via an unbounded strcpy into a fixed 256-byte stack buffer when handling TYPEPTR queries. The overflow is possible because dnexpand converts non-printable ASCII bytes (e.g., 0x01) into multi-character octal representations (e.g., \001), significantly inflating the expanded name beyond the stack buffer's capacity. A crafted DNS packet can exploit this expansion behavior to overflow the stack buffer, making the vulnerability reachable through normal multicast DNS packet processing. This issue has been fixed in versions 24.10.6 and 25.12.1.

Assessment

CVSS: 9.5 (v4.0)
Severity: Critical
EPSS: 1.26% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 19 March 2026
Last updated: 3 November 2026
Affected: OpenWRT · OpenWRT
Assigner: GitHub_M

CVSS vectorCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

At the source

EUVD (ENISA)

References

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