{"id":"CVE-2020-17527","revision":null,"records":[{"revision":"4ad7a43e17d6466ba95ad5068b4faf1c","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2020-17527","aliases":[],"title":"Apache Tomcat: Request header mix-up between HTTP/2 streams","description":"While investigating bug 64830 it was discovered that Apache Tomcat 10.0.0-M1 to 10.0.0-M9, 9.0.0-M1 to 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.","state":0,"publishedAt":"2020-12-03T18:30:14+00:00","modifiedAt":"2026-10-08T21:13:51.17+00:00","affected":[{"ecosystem":"Vendor product","name":"Apache Tomcat","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Apache Tomcat\",\n                    \"vendor\": \"Apache Software Foundation\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"Apache Tomcat 10 10.0.0-M1 to 10.0.0-M9\"\n                        },\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"Apache Tomcat 9 9.0.0-M1 to 9.0.39\"\n                        },\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"Apache Tomcat 8.5 8.5.0 to 8.5.59\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://lists.apache.org/thread.html/rce5ac9a40173651d540babce59f6f3825f12c6d4e886ba00823b11e5%40%3Cannounce.tomcat.apache.org%3E","https://lists.apache.org/thread.html/r8a227ac6a755a6406c1cc47dd48800e973d4cf13fe7fe68ac59c679c%40%3Cdev.tomcat.apache.org%3E","https://lists.apache.org/thread.html/raa0e9ad388c1e6fd1e301b5e080f9439f64cb4178119a86a4801cc53%40%3Cdev.tomcat.apache.org%3E","https://lists.apache.org/thread.html/rce5ac9a40173651d540babce59f6f3825f12c6d4e886ba00823b11e5%40%3Cannounce.apache.org%3E","https://lists.apache.org/thread.html/rd5babd13d7a350b369b2f647b4dd32ce678af42f9aba5389df1ae6ca%40%3Cusers.tomcat.apache.org%3E","http://www.openwall.com/lists/oss-security/2020/12/03/3","https://lists.apache.org/thread.html/rabbe6b3ae6a9795641d7a05c00d2378d5bbbe4240b7e20f09b092cce%40%3Cissues.guacamole.apache.org%3E","https://lists.apache.org/thread.html/ra35c8d617b17d59f400112cebadec43ad379f98198b4a9726190d7ee%40%3Cissues.guacamole.apache.org%3E","https://lists.apache.org/thread.html/r9fd47f1b03e9b41d16a5cf72659b533887267d3398d963c2fff3abfa%40%3Ccommits.tomee.apache.org%3E","https://lists.apache.org/thread.html/r26a2a66339087fc37db3caf201e446d3e83b5cce314371e235ff1784%40%3Ccommits.tomee.apache.org%3E","https://lists.debian.org/debian-lts-announce/2020/12/msg00022.html","https://security.gentoo.org/glsa/202012-23","https://lists.apache.org/thread.html/rca833c6d42b7b9ce1563488c0929f29fcc95947d86e5e740258c8937%40%3Cdev.tomcat.apache.org%3E","https://lists.apache.org/thread.html/ra9fcdb904dd2e2256ef90b3e4ced279cd464cb0ab63a6c64df5c010d%40%3Cannounce.apache.org%3E","https://lists.apache.org/thread.html/r5a285242737ddef4d338236328aaaf3237183e1465a5efafd16b99ed%40%3Cdev.tomcat.apache.org%3E","https://lists.apache.org/thread.html/ra9fcdb904dd2e2256ef90b3e4ced279cd464cb0ab63a6c64df5c010d%40%3Cannounce.tomcat.apache.org%3E","https://lists.apache.org/thread.html/rbba08c4dcef3603e36276d49adda8eedbe458c5104314b4038f697e1%40%3Cusers.tomcat.apache.org%3E","https://www.debian.org/security/2021/dsa-4835","https://lists.apache.org/thread.html/r2d6e05c5ff96f8068a59dfdb3800e9ee8d4e36ce1971783c6e5f9b20%40%3Ccommits.tomee.apache.org%3E","https://www.oracle.com/security-alerts/cpuApr2021.html","https://security.netapp.com/advisory/ntap-20201210-0003/","https://www.oracle.com//security-alerts/cpujul2021.html","https://www.oracle.com/security-alerts/cpujan2022.html","https://www.oracle.com/security-alerts/cpuapr2022.html"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2020-17527","license":"CVE Program Terms of Use","key":"cve-program:CVE-2020-17527","identifiers":["CVE-2020-17527"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. 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