Security」タグアーカイブ

Nginx: Let’s EncryptのTLS/SSL証明書の更新方法

3ヶ月ほど前に本ブログのサーバを更改の上、https化対応を実施。TLS証明書についてはフリーのLet’s Encryptより発行したが、当該証明書の有効期間は90日である為、先日初回の更新を行った。本記事はその際の作業手順を記載したもの。

続きを読む

Tully's Coffee Nishi-Shinjuku in Tokyo: One of Recommended Cafe in Shinjuku area

metro_wifi_tullys_nishi-shinjuku
This cafe is very convenient for me to get free Wi-Fi and it is called “METRO FREE Wi-Fi“, because it is close to Nishi-Shinjuku metro station. By the way, before users are authorized by the server, users can send ping any destination but aren’t allowed to transfer any TCP/IP packets. It’s to be expected that the provider wants to restrict the unauthorized user to prevent any unexpected and malicious behavior.

Logs of ping and ssh before I start to authorize:

SECCON2014: CTF (Capture the flag) competition of security in Japan

seccon2014_xss_stage9
I participated in SECCON at the Japanese competition of information security with my colleagues as a team in 19th, July. The final ranking was 43 out of 425 teams.
(Japanese official site)

We started from 9:00 and ended at 21:00 (12 hours!) so I was very exhausted but I was so excited when I was able to solve the parts of some problems. Moreover, I could improve my security skills and recognize my weak points in the field. It was a very valuable event. When I have a chance to attend such competition in the near future, I’ll participate again and of course, I’ll prepare by improving my skill every day to contribute.