{"id":"CVE-2026-67298","summary":"FreeRDP 3.28.0 Heap Buffer Overflow via RAIL orderLength Underflow","details":"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_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.","modified":"2026-09-05T11:11:33.898321006Z","published":"2026-08-01T12:22:18.323Z","related":["ALSA-2026:61378","GHSA-5wr6-8m8j-3h7f","GHSA-qmvw-52ph-q5pv"],"database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-191"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67298.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67298.json"},{"type":"ADVISORY","url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmvw-52ph-q5pv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67298"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-via-rail-orderlength-underflow"},{"type":"FIX","url":"https://github.com/FreeRDP/FreeRDP/commit/46848765f2a1134f8652f8760eefb5e85d64a9b8"},{"type":"FIX","url":"https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f"},{"type":"EVIDENCE","url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-5wr6-8m8j-3h7f"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/freerdp/freerdp","events":[{"introduced":"0"},{"fixed":"46848765f2a1134f8652f8760eefb5e85d64a9b8"},{"fixed":"5370fb26fbf034ecd11d3026b6ad639b5fff493f"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"3.29.0"}]}}],"versions":["3.5.1","3.5.0","3.4.0","3.3.0","3.2.0","3.1.0","3.0.0","3.0.0-rc0","3.0.0-beta4","3.0.0-beta3","3.0.0-beta2","3.0.0-beta1","2.0.0","2.0.0-rc4","2.0.0-rc3","2.0.0-rc2","2.0.0-rc1","2.0.0-rc0","2.0.0-beta1+android11","2.0.0-beta1+android10","1.2.0-beta1+android9","1.2.0-beta1+android7","1.1.0-beta+2013071101","1.1.0-beta1+ios4","1.1.0-beta1+android5","1.1.0-beta1+android4","1.1.0-beta1+ios3","1.1.0-beta1+ios2","1.1.0-beta1+android3","1.1.0-beta1+android2","1.1.0-beta1+ios1","1.1.0-beta1","1.0.1","1.0.0","1.0-beta5","1.0-beta4","1.0-beta2","1.0-beta1"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-67298.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}