TMA-BIND-3.2
Restrict Recursive Queries
Mô tả
A recursive DNS query is your typical DNS query from a client to a caching DNS server. It places the burden of finding the answer on the caching DNS server which will recursively query other DNS servers authoritative for the domains, until it gets the answer which is then returned to the client. The audit passes when the global options set "recursion no;" or an allow-recursion list that does not contain any. The audit parses the effective configuration printed by named-checkconf -p (all include files resolved) from /etc/named.conf (RHEL; chroot /var/named/chroot is detected) or /etc/bind/named.conf (Debian/Ubuntu).
Cách kiểm tra
Phương pháp kiểm tra: Lệnh shell
if [ -f /var/named/chroot/etc/named.conf ]; then out=$(named-checkconf -t /var/named/chroot -p /etc/named.conf 2>/dev/null) || exit 1
else conf=/etc/named.conf; [ -f "$conf" ] || conf=/etc/bind/named.conf
out=$(named-checkconf -p "$conf" 2>/dev/null) || exit 1; fi
flat=$(printf '%s\n' "$out" | tr '\t\n' ' ' | tr -s ' ')
opts=$(printf '%s\n' "$out" | awk '/^options[ \t]*\{/{f=1} f{print} f&&/^\};/{exit}' | tr '\t\n' ' ' | tr -s ' ')
if printf '%s\n' "$opts" | grep -Eq '[{; ]recursion no;'; then echo compliant; exit 0; fi
ar=$(printf '%s\n' "$opts" | grep -Eo 'allow-recursion \{[^}]*\}') || { echo 'recursion enabled without allow-recursion'; exit 1; }
printf '%s\n' "$ar" | grep -Eq '[{ ]"?any"?;' && { echo 'allow-recursion contains any'; exit 1; }
echo compliant- Đầu ra mong đợi
compliant
Cách khắc phục
Phương pháp khắc phục: Hướng dẫn hoặc bản vá hạ tầng
Authoritative Name Server: For an authoritative name server, insert one of the following either into the global options or into every zone section. allow-recursion { localhost; }; recursion no; Caching Name Server: ; Define an ACL named trusted_clients which will identify the networks which are expected to use the DNS caching server, and will be allowed to send recursive DNS queries. acl trusted_clients { 10.19.4.0/28; . . . } ; Insert the following into the global options. allow-recursion { localhost; trusted_clients };
Thuộc tính
- Hệ điều hành
- Bất kỳ
- Thẻ
- binddnsaccess-control
- Tham chiếu
- CIS ISC BIND DNS Server 9.11 Benchmark v1.0.0 - 3.2 Restrict Recursive Queries
Kiểm tra máy này
Chạy lệnh này trên máy bạn được phép kiểm tra. Lần quét chỉ ở chế độ đọc.
tmaegis scan --target bind