{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7418bc7b7c880a87edade60282f6aeeacd640e47"
            }
          ],
          "repo": "https://github.com/freerdp/freerdp",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-qmqf-m84q-x896"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-125",
      "CWE-758"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/22xxx/CVE-2026-22858.json"
  },
  "details": "FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.20.1, global-buffer-overflow was observed in FreeRDP's Base64 decoding path. The root cause appears to be implementation-defined char signedness: on Arm/AArch64 builds, plain char is treated as unsigned, so the guard c \u003c= 0 can be optimized into a simple c != 0 check. As a result, non-ASCII bytes (e.g., 0x80-0xFF) may bypass the intended range restriction and be used as an index into a global lookup table, causing out-of-bounds access. This vulnerability is fixed in 3.20.1.",
  "id": "CVE-2026-22858",
  "modified": "2026-04-01T23:08:46.822250801Z",
  "published": "2026-01-14T17:56:29.729Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/22xxx/CVE-2026-22858.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmqf-m84q-x896"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-22858"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "FreeRDP has a global-buffer-overflow in crypto_base64_decode"
}