nmap hangs during the operating system scan with IPv6. #3219
Description
Describe the bug
nmap hangs during the operating system scan with IPv6.
The normal scan finishes within hours, but the scan with operating system detection does not finish even after several days.
To Reproduce
Steps to reproduce the behavior, including command-line options.
Expected behavior
The scan is successful and ends.
Version info (please complete the following information):
- OS: Debian 13
Linux 6.12.48+deb13-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.48-1 (2025-09-20) x86_64 GNU/Linux
$ nmap --version
Nmap version 7.98SVN ( https://nmap.org )
Platform: x86_64-unknown-linux-gnu
Compiled with: liblua-5.4.7 openssl-3.5.1 libssh2-1.11.1 libz-1.3.1 libpcre2-10.46 libpcap-1.10.5 nmap-libdnet-1.18.0 ipv6
Compiled without:
Available nsock engines: epoll poll select
$ git log -n1
commit fcf6f0cb19e829720faa9f5ace506a582253104b (HEAD -> master, origin/master, origin/HEAD)
Author: nnposter <nnposter@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Wed Oct 8 23:08:04 2025 +0000
Use simpler/cheaper portrule
Additional context
log.txt
ipv6_scan.sh
alive_addresses.txt
2025_10_12_ipv6_dn42_port_scan_nmap_scan.xml
2025_10_12_ipv6_dn42_port_scan_nmap_scan.nmap.txt