{"id":"CVE-2026-41293","title":"tomcat-coyote: Apache Tomcat: HTTP/2 request headers not validated (CVE-2026-41293)","summary":"Apache Tomcat did not validate HTTP/2 request headers, triggering unexpected application behavior, as applications may presume that header values exposed through the Servlet API would be valid.","severity":"high","cvss":7.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L","cvssSource":"vendor","cwe":["CWE-1286","CWE-20"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux AppStream EUS (v. 10.0)","affected":["enterprise_linux 6","enterprise_linux 8","enterprise_linux 9","jboss_web_server 5","jboss_web_server_6_2_on_rhel 10","jboss_web_server_7_0_on_rhel 10","jboss_web_server_6_2_on_rhel 8","jboss_web_server_7_0_on_rhel 8","jboss_web_server_6_2_on_rhel 9","jboss_web_server_7_0_on_rhel 9","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_v_10","enterprise_linux_appstream_v_8","enterprise_linux_appstream_e4s_v_8_8","enterprise_linux_appstream_tus_v_8_8","enterprise_linux_appstream_e4s_v_9_2","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6","enterprise_linux_appstream_v_9","jboss_web_server 6.2.4","jboss_web_server 7.0.0"],"patched":["jboss_web_server_6_2_on_rhel 10","jboss_web_server_7_0_on_rhel 10","jboss_web_server_6_2_on_rhel 8","jboss_web_server_7_0_on_rhel 8","jboss_web_server_6_2_on_rhel 9","jboss_web_server_7_0_on_rhel 9","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_v_10","enterprise_linux_appstream_v_8","enterprise_linux_appstream_e4s_v_8_8","enterprise_linux_appstream_tus_v_8_8","enterprise_linux_appstream_e4s_v_9_2","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6","enterprise_linux_appstream_v_9","jboss_web_server 6.2.4","jboss_web_server 7.0.0"],"published":"2026-05-12","updated":"2026-09-21","sourceUpdated":"2026-09-21T17:17:08+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41293.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41293.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-41293"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2476513"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-41293"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41293"},{"url":"https://lists.apache.org/thread/qwg0q16z7xkb2qrr853wdll5531mvl1r"},{"url":"https://access.redhat.com/errata/RHSA-2026:43401"},{"url":"https://access.redhat.com/errata/RHSA-2026:39188"},{"url":"https://access.redhat.com/errata/RHSA-2026:67164"},{"url":"https://access.redhat.com/errata/RHSA-2026:67163"},{"url":"https://access.redhat.com/errata/RHSA-2026:69259"},{"url":"https://access.redhat.com/errata/RHSA-2026:68651"},{"url":"https://access.redhat.com/errata/RHSA-2026:68677"},{"url":"https://access.redhat.com/errata/RHSA-2026:68680"},{"url":"https://access.redhat.com/errata/RHSA-2026:68678"},{"url":"https://access.redhat.com/errata/RHSA-2026:68679"},{"url":"https://access.redhat.com/errata/RHSA-2026:68659"},{"url":"https://access.redhat.com/errata/RHSA-2026:68660"},{"url":"https://access.redhat.com/errata/RHSA-2026:43402"},{"url":"https://access.redhat.com/errata/RHSA-2026:39189"}],"tags":["csaf","vex","red-hat","exploit-available","cve.org","score-dispute"],"epss":0.0168,"epssPercentile":0.75538,"exploits":{"github":1,"githubRepos":["https://github.com/xiaoqiMikko/tomcat-check"],"checkedAt":"2026-09-22T07:31:20.127Z"},"exploitAvailable":true,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-05-14T16:40:13.006509Z"},"scores":{"vendor":7.3,"adp":9.8},"ingestedAt":"2026-09-17T19:26:25.352Z","slug":"CVE-2026-41293","body":"## Overview\n\nApache Tomcat did not validate HTTP/2 request headers, triggering unexpected application behavior, as applications may presume that header values exposed through the Servlet API would be valid.\n\n## Vendor advisories\n\n- **RHSA-2026:43401** · Red Hat · fixed in: Red Hat JBoss Web Server 6.2 on RHEL 10, Red Hat JBoss Web Server 6.2 on RHEL 8, Red Hat JBoss Web Server 6.2 on RHEL 9 · released 2026-07-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:43401)\n- **RHSA-2026:39188** · Red Hat · fixed in: Red Hat JBoss Web Server 7.0 on RHEL 10, Red Hat JBoss Web Server 7.0 on RHEL 8, Red Hat JBoss Web Server 7.0 on RHEL 9 · released 2026-07-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:39188)\n- **RHSA-2026:67164** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67164)\n- **RHSA-2026:67163** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67163)\n- **RHSA-2026:69259** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69259)\n- **RHSA-2026:68651** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-09-18 · [advisory](https://access.redhat.com/errata/RHSA-2026:68651)\n- **RHSA-2026:68677** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68677)\n- **RHSA-2026:68680** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68680)\n- **RHSA-2026:68678** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68678)\n- **RHSA-2026:68679** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68679)\n- **RHSA-2026:68659** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68659)\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat JBoss Web Server 5 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 6 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41293.json)\n- **RHSA-2026:68660** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68660)\n\n**tomcat-coyote: Apache Tomcat: HTTP/2 request headers not validated** — rated Moderate by Red Hat. Released 2026-05-12, updated 2026-09-21.\n\nAffected:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat JBoss Web Server 5\n\nFixed:\n\n- Red Hat JBoss Web Server 6.2 on RHEL 10\n- Red Hat JBoss Web Server 7.0 on RHEL 10\n- Red Hat JBoss Web Server 6.2 on RHEL 8\n- Red Hat JBoss Web Server 7.0 on RHEL 8\n- Red Hat JBoss Web Server 6.2 on RHEL 9\n- Red Hat JBoss Web Server 7.0 on RHEL 9\n- Red Hat Enterprise Linux AppStream EUS (v. 10.0)\n- Red Hat Enterprise Linux AppStream (v. 10)\n- Red Hat Enterprise Linux AppStream (v. 8)\n- Red Hat Enterprise Linux AppStream E4S (v.8.8)\n- Red Hat Enterprise Linux AppStream TUS (v.8.8)\n- Red Hat Enterprise Linux AppStream E4S (v.9.2)\n- Red Hat Enterprise Linux AppStream E4S (v.9.4)\n- Red Hat Enterprise Linux AppStream EUS (v.9.6)\n- Red Hat Enterprise Linux AppStream (v. 9)\n- Red Hat JBoss Web Server 6.2.4\n- Red Hat JBoss Web Server 7.0.0\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n- Red Hat Enterprise Linux 6\n\nNot affected:\n\n- Red Hat JBoss Web Server 7.0 on RHEL 10\n- Red Hat JBoss Web Server 7.0 on RHEL 8\n- Red Hat JBoss Web Server 7.0 on RHEL 9\n- Red Hat Enterprise Linux 7\n- Red Hat Hardened Images\n\n## Remediation\n\nBefore applying this update, make sure all previously released errata relevant to your system have been applied.\n\nFor details on how to apply this update, refer to:\n\nhttps://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:43401\nBefore applying this update, make sure all previously released errata relevant to your system have been applied.\n\nFor details on how to apply this update, refer to:\n\nhttps://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:39188\nFor details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:67164","depth":"midnight","depthScore":52,"depthScoreParts":{"impact":40.2,"likelihood":0.3,"exploitation":12,"ransomware":0},"changes":[{"seq":206956,"id":"CVE-2026-41293","ts":1789749718283,"field":"cvss","old":"9.8","new":"7.3"},{"seq":206955,"id":"CVE-2026-41293","ts":1789749718283,"field":"severity","old":"critical","new":"high"}]}