{"id":54656,"date":"2026-05-14T15:36:58","date_gmt":"2026-05-14T15:36:58","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=54656"},"modified":"2026-05-14T15:36:58","modified_gmt":"2026-05-14T15:36:58","slug":"apache-tomcat-lockoutrealm-treats-user-names-as-case-sensitive","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=54656","title":{"rendered":"Apache Tomcat: LockOutRealm treats user names as case-sensitive_CVE-2026-43513"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Improper Handling of Case Sensitivity vulnerability in LockOutRealm in Apache Tomcat.\\n\\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109.\\nOlder unsupported versions may also be affected.\\n\\nUsers are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.&#8221;,&#8221;published&#8221;:&#8221;2026-05-12T15:26:25.599Z&#8221;,&#8221;modified&#8221;:&#8221;2026-05-14T19:53:30.781Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Apache Tomcat: LockOutRealm treats user names as case-sensitive&#8221;,&#8221;source&#8221;:&#8221;apache&#8221;,&#8221;references&#8221;:&#8221;https:\/\/lists.apache.org\/thread\/ytjcgldshj73lcnd1sh95od5hrghwogp&#8221;,&#8221;id&#8221;:&#8221;CVE-2026-43513&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-178&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;Apache Software Foundation Apache Tomcat 11.0.0-M1\\nApache Software Foundation Apache Tomcat 10.1.0-M1\\nApache Software Foundation Apache Tomcat 9.0.0.M1\\nApache Software Foundation Apache Tomcat 8.5.0\\nApache Software Foundation Apache Tomcat 7.0.0&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:7.5,&#8221;severity&#8221;:&#8221;HIGH&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:N\/UI:N\/S:U\/C:H\/I:N\/A:N&#8221;,&#8221;version&#8221;:&#8221;3.1&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;Apache Tomcat&#8221;,&#8221;version&#8221;:&#8221;11.0.0-M1&#8243;,&#8221;vendor&#8221;:&#8221;Apache Software Foundation&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Improper Handling of Case Sensitivity vulnerability in LockOutRealm in Apache Tomcat.\\n\\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,16,12,15,13,7,11,5],"class_list":["post-54656","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-75","tag-exploit","tag-high","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - 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