{"id":"CVE-2026-40033","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-40033","generatedAt":"2026-10-28T04:41:05.112Z","title":"FreeRDP before 3.26.0 contains a heap-buffer-overflow vulnerability in gdi_CacheToSurface that allows remote attackers to write out-of-bounds heap memory.","description":"FreeRDP before 3.26.0 contains a heap-buffer-overflow vulnerability in gdi_CacheToSurface that allows remote attackers to write out-of-bounds heap memory. The vulnerability occurs because rectangle validation clamps coordinates to UINT16_MAX but performs copy operations using unclamped cache entry dimensions, enabling malicious RDP servers to trigger large out-of-bounds writes and potentially achieve remote code execution or client crash.","published":"2026-05-26T15:16:34.000Z","lastModified":"2026-07-27T13:17:55.000Z","status":"Modified","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":8.7,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-122","CWE-787"],"affected":["freerdp/freerdp"],"epss":{"score":0.01365,"percentile":0.71665,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/FreeRDP/FreeRDP/commit/d7508ebcd82842a691ae4941e5104d14240a89ae","source":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/pull/12713","source":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-in-gdi-cachetosurface-via-rectangle-validation-bypass","tags":["Third Party Advisory"],"source":"disclosure@vulncheck.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:36203","source":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:46393","source":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-40033","source":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2481473","source":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40033.json","source":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-40033","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}