{"id":"CVE-2026-44421","state":"PUBLISHED","title":"FreeRDP RDPGFX CacheToSurface heap-buffer-overflow via clamped-rectangle validation bypass","description":"FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.","publishedAt":"2026-05-29T19:40:25.492Z","updatedAt":"2026-07-27T12:05:30.051Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["FreeRDP FreeRDP"],"affected":[{"vendor":"FreeRDP","product":"FreeRDP","versions":[{"version":"< 3.26.0","status":"affected"}]}],"references":["https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","https://access.redhat.com/security/cve/CVE-2026-44421","https://bugzilla.redhat.com/show_bug.cgi?id=2483471","https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44421.json","https://access.redhat.com/errata/RHSA-2026:46393","https://access.redhat.com/errata/RHSA-2026:36203"],"weaknesses":["CWE-122","CWE-787"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/44xxx/CVE-2026-44421.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44421","state":"PUBLISHED","datePublished":"2026-05-29T19:40:25.492Z","dateUpdated":"2026-07-27T12:05:30.051Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-06T14:40:00.953Z"},"containers":{"cna":{"title":"FreeRDP RDPGFX CacheToSurface heap-buffer-overflow via clamped-rectangle validation bypass","descriptions":[{"lang":"en","value":"FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0."}],"affected":[{"vendor":"FreeRDP","product":"FreeRDP","versions":[{"version":"< 3.26.0","status":"affected"}]}],"references":[{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","name":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-122","lang":"en","description":"CWE-122: Heap-based Buffer Overflow","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-29T19:40:25.492Z"},"source":{"advisory":"GHSA-p6r2-4hgm-m6ff","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-01T00:00:00+00:00","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2026-44421"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-02T03:55:49.461Z"}},{"title":"freerdp: FreeRDP: Arbitrary code execution via crafted RDPGFX PDUs","descriptions":[{"lang":"en","value":"A heap-buffer-overflow vulnerability exists in FreeRDP when handling Remote Desktop Protocol Graphics (RDPGFX). A malicious or compromised RDP server can exploit this flaw by sending specially crafted graphics packets to a connected client, potentially crashing the client application (Denial of Service) or executing arbitrary code on the user's machine."}],"affected":[{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","packageName":"freerdp","defaultStatus":"affected","versions":[{"version":"2:3.10.3-12.el10_2.6","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:10.2"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","packageName":"freerdp","defaultStatus":"unknown","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:6"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"freerdp","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","packageName":"freerdp","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","packageName":"freerdp","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:9"]}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-44421","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2483471","name":"RHBZ#2483471","tags":["issue-tracking","x_refsource_REDHAT"]},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44421.json","tags":["x_sadp-csaf-vex"]},{"url":"https://access.redhat.com/errata/RHSA-2026:46393","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:36203","tags":["vendor-advisory","x_refsource_REDHAT"]}],"metrics":[{"other":{"content":{"namespace":"https://access.redhat.com/security/updates/classification/","value":"Important"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","version":"3.1"},"format":"CVSS"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-787","description":"Out-of-bounds Write","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"redhat-SADP","orgId":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c","dateUpdated":"2026-07-27T12:05:30.051Z"},"datePublic":"2026-05-29T19:40:25.492Z","solutions":[{"lang":"en","value":"RHSA-2026:46393: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)"},{"lang":"en","value":"RHSA-2026:36203: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)"}],"timeline":[{"lang":"en","time":"2026-05-29T21:01:24.644Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-05-29T19:40:25.492Z","value":"Made public."}],"workarounds":[{"lang":"en","value":"To mitigate this vulnerability, disable the RDPGFX graphics acceleration feature in your FreeRDP client configuration. Additionally, avoid using FreeRDP to connect to untrusted or unknown external servers. This may cause a temporary disruption in service for your users."}],"x_adpType":"supplier","x_generator":{"engine":"sadp-cli 1.0.0"}}]}}}