1. Description of Security Vulnerabilities
Products that use Nginx to provide services, after being scanned by security scanning tools, three high-risk and three medium-risk security vulnerabilities are reported
2. The version of nginx is too low and comes with security holes
After upgrading the nginx version to 1.21.1, the three high-risk vulnerabilities disappeared.
3. HTTP header disclosure
- Download the source code:
http://nginx.org/en/download.html
- Modify the source code:
There are three source code locations that need to be modified to modify the Server header:
nginx.h file in the src/core directory
ngx_http_header_filter_module.c file in the src/http directory
The ngx_http_special_response.c file in the src/http directory
- Compile:
./configure --prefix=/etc/nginx --sbin-path=/usr/sbin/nginx --modules-path=/usr/lib/nginx/modules --conf-path=/etc/nginx/nginx.conf --error-log-path=/var/log/nginx/error.log --http-log-path=/var/log/nginx/access.log --pid-path=/var/run/nginx.pid --lock-path=/var/run/nginx.lock --http-client-body-temp-path=/var/cache/nginx/client_temp --http-proxy-temp-path=/var/cache/nginx/proxy_temp --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp--http-scgi-temp-path=/var/cache/nginx/scgi_temp --user=nginx --group=nginx --with-compat --with-file-aio --with-threads --with-http_addition_module --with-http_auth_request_module --with-http_dav_module --with-http_flv_module --with-http_gunzip_module --with-http_gzip_static_module --with-http_mp4_module --with-http_random_index_module --with-http_realip_module --with-http_secure_link_module --with-http_slice_module --with-http_ssl_module --with-http_stub_status_module --with-http_sub_module --with-http_v2_module --with-mail --with-mail_ssl_module --with-stream --with-stream_realip_module --with-stream_ssl_module --with-stream_ssl_preread_module --with-cc-opt='-g -O2 -fdebug-prefix-map=/data/builder/debuild/nginx-1.21.1/debian/debuild-base/nginx-1.21.1=. -fstack-protector-strong -Wformat -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fPIC' --with-ld-opt='-Wl,-z,relro -Wl,-z,now -Wl,--as-needed -pie'
make
Encoding errors are mostly due to missing components, just install them.
- If the compilation is successful, the nginx binary file will be generated in the objs directory, and replace /usr/sbin/nginx or put it in /usr/sbin.
final effect:
4. Error page information exposure
Error page redirection, custom 404 error page.
Effect:
5. Disable server token
Set in the nginx configuration file: server_tokens off