{"cve":"CVE-2026-22858","nvd":{"published":"2026-01-14T18:16:43.520","modified":"2026-07-15T02:18:38.407","status":"Modified","description":"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 <= 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.","cvss_v4":{"vector":"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","score":5.6},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","score":9.1},"cwes":["CWE-125","CWE-758","CWE-787"],"references":["https://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1","https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmqf-m84q-x896","https://access.redhat.com/errata/RHSA-2026:19033","https://access.redhat.com/errata/RHSA-2026:3067","https://access.redhat.com/errata/RHSA-2026:3068"],"products":["freerdp:freerdp"],"source":"nvd","synced_at":"2026-10-19T22:19:41.481987139+00:00"},"epss":{"cve":"CVE-2026-22858","score":0.00703,"percentile":0.53314,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}