{"id":"CVE-2026-67298","title":"FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c)","summary":"FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PD…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-191"],"published":"2026-08-01","updated":"2026-08-01","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-67298","references":[{"url":"https://github.com/FreeRDP/FreeRDP/commit/46848765f2a1134f8652f8760eefb5e85d64a9b8","label":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f","label":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmvw-52ph-q5pv","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-via-rail-orderlength-underflow","label":"disclosure@vulncheck.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67298.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-67298"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2510041"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-67298"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67298"},{"url":"https://access.redhat.com/errata/RHSA-2026:61378"},{"url":"https://access.redhat.com/errata/RHSA-2026:68707"},{"url":"https://access.redhat.com/errata/RHSA-2026:68706"}],"tags":["nvd","csaf","vex","red-hat"],"ingestedAt":"2026-08-02T05:17:49.662Z","epss":0.00376,"epssPercentile":0.31343,"vendor":"Red Hat","product":"Red Hat Enterprise Linux AppStream (v. 10)","affected":["enterprise_linux 6","enterprise_linux 7","enterprise_linux_appstream_v_10","enterprise_linux_codeready_linux_builder_v_10"],"patched":["enterprise_linux_appstream_v_10","enterprise_linux_codeready_linux_builder_v_10"],"scores":{"nvd":7.5,"vendor":7.1},"slug":"CVE-2026-67298","body":"## Overview\n\nFreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:61378** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-08-31 · [advisory](https://access.redhat.com/errata/RHSA-2026:61378)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-09-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67298.json)\n- **RHSA-2026:68707** · Red Hat · fixed in: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68707)\n- **RHSA-2026:68706** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68706)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}