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TI-2026-23701 Aliases CVE-2026-30872

OpenWrt Project has a Stack-based Buffer Overflow vulnerability via IPv6 reverse DNS lookup

Priority MEDIUM 53CWE-121Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02359 83rd percentileScored 2026-11-07
Fix Fixed openwrt (openwrt): 25.12.1, 24.10.6

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
openwrtopenwrt25.12.0-rc1 to before 25.12.1; before 24.10.625.12.1, 24.10.6Patch availableCNA
  • openwrt Vendoropenwrt Affected 25.12.0-rc1 to before 25.12.1; before 24.10.6 Fixed in 25.12.1, 24.10.6 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:openwrt:openwrt:*:*:*:*:*:*:*:*before 24.10.6; 25.12.0 to before 25.12.1Vulnerableopenwrt
  • cpe:2.3:o:openwrt:openwrt:*:*:*:*:*:*:*:* Versions before 24.10.6; 25.12.0 to before 25.12.1 Vulnerable ·openwrt

Remediation

  • Fix · CNA openwrt (openwrt) Fixed in 25.12.1, 24.10.6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-30872
  2. 2026-11-03 CISA SSVC decision points changed

References

Advisory 1

Other 2

  • TI-2024-13053 Improper input validation in MediaTek MT6890, MT7915, MT7916, MT7981, MT7986 CVSS 3.1CRITICAL 9.8
  • TI-2026-44983 Cross-site scripting in openwrt CVSS 3.1CRITICAL 9.6
  • TI-2026-40045 OpenWrt: EAD Integer Underflow → Pre-Auth Denial of Service CVSS 3.1MEDIUM 6.5
  • TI-2023-09914 LuCI openwrt-22.03 branch git-22.361.69894-438c598 was discovered to contain a stored… CVSS 3.1MEDIUM 5.4
  • TI-2026-44982 OpenWrt: ACL bypass and arbitrary root file read via cgi-io cgi-download CVSS 3.1MEDIUM 4.9
  • TI-2026-23700 OpenWrt Project has Stack-based Buffer Overflow in DNS PTR Query CVSS 4.0CRITICAL 9.5
See all 136 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences