UCloud-202310-003:HTTP/2 协议拒绝服务漏洞安全警告

漏洞详情

互联网上公开了近几个月利用 HTTP/2 协议拒绝服务漏洞(CVE-2023-44487)进行攻击的详细信息。恶意攻击者可通过打开多个请求流并立即通过发送RST_STREAM帧,取消请求,通过这种办法可以绕过并发流的限制,导致服务器资源的快速消耗。鉴于此漏洞影响产品较多,并已存在在野利用,建议客户尽快做好自查及防护。

影响范围

软件

受影响版本

Netty

Netty < 4.1.100.Final

Go

Go < 1.21.3

Go < 1.20.10

Apache Tomcat

11.0.0-M1 <= Apache Tomcat <= 11.0.0-M11

10.1.0-M1 <= Apache Tomcat <= 10.1.13

9.0.0-M1 <= Apache Tomcat <= 9.0.80

8.5.0 <= Apache Tomcat <= 8.5.93

grpc-go

grpc-go < 1.58.3

grpc-go < 1.57.1

grpc-go < 1.56.3

jetty

jetty < 12.0.2

jetty < 10.0.17

jetty < 11.0.17

jetty < 9.4.53.v20231009

nghttp2

nghttp2 < v1.57.0

Apache Traffic Server

8.0.0 <= Apache Traffic Server <= 8.1.8

9.0.0 <= Apache Traffic Server <= 9.2.2

ps:*默认配置下Nginx允许客户端最多保持1000个HTTP连接,依赖此限制Nginx默认可防护此类攻击。同时需注意的是,若配置keepalive_requests值远高于默认值,则同样可能受到此漏洞影响。

修复方案

注意:安装升级前,请做好数据备份、快照和测试工作,防止发生意外

软件修复版本

下载信息

Netty >= 4.1.100.Final

https://github.com/netty/netty/releases/tag/netty-4.1.100.Final

Go >= 1.21.3、1.20.10

https://github.com/golang/go/tags

Apache Tomcat >= 11.0.0-M12、10.1.14、9.0.81、8.5.94

https://tomcat.apache.org/security-11.html#Fixed_in_Apache_Tomcat_11.0.0-M12

https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.14

https://tomcat.apache.org/security-9.html#Fixed_in_Apache_Tomcat_9.0.81

https://tomcat.apache.org/security-8.html#Fixed_in_Apache_Tomcat_8.5.94

grpc-go >= 1.58.3、1.57.1、1.56.3

https://github.com/grpc/grpc-go/releases

jetty >= 12.0.2、10.0.17、11.0.17、9.4.53.v20231009

https://github.com/eclipse/jetty.project/releases

nghttp2 >= v1.57.0

https://github.com/nghttp2/nghttp2/releases

Apache Traffic Server >= 8.1.9、9.2.3

https://github.com/apache/trafficserver/tags

NGINX

https://github.com/nginx/nginx

缓解措施

启用UCloud安全产品web应用防火墙UWAF、DDoS攻击防护和UClean;

避免将应用完全暴露至公网;

在Web服务上禁用HTTP2协议(这个会影响系统性能);

参考链接

https://seclists.org/oss-sec/2023/q4/75

https://www.openwall.com/lists/oss-security/2023/10/10/6

https://www.nginx.com/blog/http-2-rapid-reset-attack-impacting-f5-nginx-products/