{"id":11480,"date":"2021-08-19T14:12:20","date_gmt":"2021-08-19T05:12:20","guid":{"rendered":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/?p=11480"},"modified":"2023-10-17T11:43:34","modified_gmt":"2023-10-17T02:43:34","slug":"isc-bind-9%e3%81%ae%e8%84%86%e5%bc%b1%e6%80%a7%ef%bc%88cve-2021-25218%ef%bc%89%e3%81%ab%e9%96%a2%e3%81%99%e3%82%8b%e6%b3%a8%e6%84%8f%e5%96%9a%e8%b5%b7","status":"publish","type":"post","link":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/public\/heads-up\/isc-bind-9%e3%81%ae%e8%84%86%e5%bc%b1%e6%80%a7%ef%bc%88cve-2021-25218%ef%bc%89%e3%81%ab%e9%96%a2%e3%81%99%e3%82%8b%e6%b3%a8%e6%84%8f%e5%96%9a%e8%b5%b7\/","title":{"rendered":"ISC BIND 9\u306e\u8106\u5f31\u6027\uff08CVE-2021-25218\uff09\u306b\u95a2\u3059\u308b\u6ce8\u610f\u559a\u8d77"},"content":{"rendered":"\n

I. \u6982\u8981
ISC BIND 9\u306b\u306f\u3001\u5fdc\u7b54\u901f\u5ea6\u5236\u9650\uff08RRL\uff09\u304c\u6709\u52b9\u306a\u5834\u5408\u306b\u3001named\u304c\u6709\u52b9\u306a\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9\u306e\u6700\u5927\u8ee2\u9001\u5358\u4f4d\uff08MTU\uff09\u3088\u308a\u3082\u5927\u304d\u3044\u5fdc\u7b54\u3092\u884c\u3063\u305f\u969b\u306b\u30a2\u30b5\u30fc\u30b7\u30e7\u30f3\u30a8\u30e9\u30fc\u3092\u5f15\u304d\u8d77\u3053\u3059\u8106\u5f31\u6027\u304c\u3042\u308a\u307e\u3059\u3002
\u8106\u5f31\u6027\u304c\u60aa\u7528\u3055\u308c\u308b\u3068\u3001\u9060\u9694\u306e\u7b2c\u4e09\u8005\u304cnamed\u3092\u7570\u5e38\u7d42\u4e86\u3055\u305b\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002
\u53c2\u8003\uff1ahttps:\/\/www.jpcert.or.jp\/at\/2021\/at210035.html<\/a><\/p>\n

ISC\u306f\u3001\u672c\u8106\u5f31\u6027\u306b\u5bfe\u3059\u308b\u6df1\u523b\u5ea6\u3092\u300c\u9ad8\uff08High\uff09\u300d\u3068\u8a55\u4fa1\u3057\u3066\u3044\u307e\u3059\u3002
\u8106\u5f31\u6027\u306e\u8a73\u7d30\u306fISC\u306e\u60c5\u5831\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n

Internet Systems Consortium, Inc.\uff08ISC\uff09
CVE-2021-25218: A too-strict assertion check could be triggered when responses in BIND 9.16.19 and 9.17.16 require UDP fragmentation if RRL is in use
https:\/\/kb.isc.org\/docs\/cve-2021-25218<\/p>\n

\u5f71\u97ff\u3092\u53d7\u3051\u308b\u30d0\u30fc\u30b8\u30e7\u30f3\u306eISC BIND 9\u3092\u904b\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u300cIII.\u5bfe\u7b56\u300d\u3092\u53c2\u8003\u306b\u4fee\u6b63\u6e08\u307f\u30d0\u30fc\u30b8\u30e7\u30f3\u306e\u9069\u7528\u306b\u3064\u3044\u3066\u691c\u8a0e\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n


II. \u5bfe\u8c61
\u5bfe\u8c61\u3068\u306a\u308b\u88fd\u54c1\u3068\u30d0\u30fc\u30b8\u30e7\u30f3\u306f\u6b21\u306e\u3068\u304a\u308a\u3067\u3059\u3002<\/p>\n

– BIND 9.17.16
– BIND 9.16.19
– BIND 9 Supported Preview Edition 9.16.19-S1<\/p>\n

\u672c\u8106\u5f31\u6027\u306f\u3001\u4e0a\u8a18\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306e\u307f\u5f71\u97ff\u3092\u53d7\u3051\u308b\u3068\u306e\u3053\u3068\u3067\u3059\u3002<\/p>\n

RRL\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306fChaos\uff08CH\uff09\u30af\u30e9\u30b9\u3067\u306e\u307f\u6709\u52b9\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002
\u30c7\u30a3\u30b9\u30c8\u30ea\u30d3\u30e5\u30fc\u30bf\u30fc\u304c\u63d0\u4f9b\u3057\u3066\u3044\u308bBIND\u3092\u304a\u4f7f\u3044\u306e\u5834\u5408\u306f\u3001\u4f7f\u7528\u4e2d\u306e\u30c7\u30a3\u30b9\u30c8\u30ea\u30d3\u30e5\u30fc\u30bf\u30fc\u306a\u3069\u306e\u60c5\u5831\u3092\u53c2\u7167\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n


III. \u5bfe\u7b56
ISC\u306f\u8106\u5f31\u6027\u3092\u4fee\u6b63\u3057\u305f\u30d0\u30fc\u30b8\u30e7\u30f3\u306eISC BIND 9\u3092\u516c\u958b\u3057\u307e\u3057\u305f\u3002
\u307e\u305f\u3001\u4eca\u5f8c\u5404\u30c7\u30a3\u30b9\u30c8\u30ea\u30d3\u30e5\u30fc\u30bf\u30fc\u306a\u3069\u3082\u3001\u4fee\u6b63\u6e08\u307f\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u3092\u63d0\u4f9b\u3059\u308b\u3068\u601d\u308f\u308c\u307e\u3059\u3002
\u5341\u5206\u306a\u30c6\u30b9\u30c8\u3092\u5b9f\u65bd\u306e\u4e0a\u3001\u66f4\u65b0\u306e\u9069\u7528\u3092\u691c\u8a0e\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n

– BIND 9.17.17
– BIND 9.16.20
– BIND Supported Preview Edition 9.16.20-S1<\/p>\n

\u306a\u304a\u56de\u907f\u7b56\u3068\u3057\u3066\u3001named.conf\u304b\u3089\u65e2\u5b58\u306e\u3059\u3079\u3066\u306erate-limit\u6587\u3092\u524a\u9664\u3057\u3001\u4ee3\u66ff\u3068\u3057\u3066\u30c7\u30d5\u30a9\u30eb\u30c8\u306eChaos\u30d3\u30e5\u30fc\u3092\u5b9a\u7fa9\u3059\u308b\u3053\u3068\u3067\u3001Chaos\u3092\u542b\u3080\u3059\u3079\u3066\u306e\u30af\u30e9\u30b9\u306eRRL\u3092\u7121\u52b9\u5316\u3059\u308b\u3053\u3068\u304c\u6319\u3052\u3089\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n


IV. \u53c2\u8003\u60c5\u5831
Internet Systems Consortium, Inc.\uff08ISC\uff09
BIND 9 Security Vulnerability Matrix
https:\/\/kb.isc.org\/docs\/aa-00913<\/a><\/p>\n

\u682a\u5f0f\u4f1a\u793e\u65e5\u672c\u30ec\u30b8\u30b9\u30c8\u30ea\u30b5\u30fc\u30d3\u30b9\uff08JPRS\uff09
\uff08\u7dca\u6025\uff09BIND 9.16.19\u306e\u8106\u5f31\u6027\uff08DNS\u30b5\u30fc\u30d3\u30b9\u306e\u505c\u6b62\uff09\u306b\u3064\u3044\u3066\uff08CVE-2021-25218\uff09- BIND 9.16.19\u306e\u307f\u304c\u5bfe\u8c61\u3001\u30d0\u30fc\u30b8\u30e7\u30f3\u30a2\u30c3\u30d7\u3092\u5f37\u304f\u63a8\u5968 –
https:\/\/jprs.jp\/tech\/security\/2021-08-19-bind9-vuln-rrl.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

I. \u6982\u8981ISC BIND 9\u306b\u306f\u3001\u5fdc\u7b54\u901f\u5ea6\u5236\u9650\uff08RRL\uff09\u304c\u6709\u52b9\u306a\u5834\u5408\u306b\u3001named\u304c\u6709\u52b9\u306a\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9\u306e\u6700\u5927\u8ee2\u9001\u5358\u4f4d\uff08MTU\uff09\u3088\u308a\u3082\u5927\u304d\u3044\u5fdc\u7b54\u3092\u884c\u3063\u305f\u969b\u306b\u30a2\u30b5\u30fc\u30b7\u30e7\u30f3\u30a8\u30e9\u30fc\u3092\u5f15\u304d\u8d77\u3053\u3059\u8106\u5f31\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u8106\u5f31\u6027\u304c\u60aa\u7528 […]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[5],"tags":[45],"_links":{"self":[{"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/posts\/11480"}],"collection":[{"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/comments?post=11480"}],"version-history":[{"count":1,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/posts\/11480\/revisions"}],"predecessor-version":[{"id":11481,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/posts\/11480\/revisions\/11481"}],"wp:attachment":[{"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/media?parent=11480"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/categories?post=11480"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.csirt.dendai.ac.jp\/csirt\/wp-json\/wp\/v2\/tags?post=11480"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}