# CVE-2026-121964: FreeRDP before 3.32.2 Heap Buffer Overflow via rpc_client_recv_fragment

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

FreeRDP before 3.32.2 contains a heap-based buffer overflow in the RD Gateway RPC client, where rpc_client_recv_fragment writes BIND_ACK and ALTER_CONTEXT_RESP fragments into a persistent PDU stream after checking only total capacity rather than remaining capacity from the current stream position. A malicious or compromised RD Gateway can send crafted RPC fragments with manipulated alloc_hint and frag_length values to overwrite client heap memory with attacker-controlled data, causing a crash or potentially arbitrary code execution.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- FreeRDP / FreeRDP: ≥ 0; < 3.32.2 (affected, semver); 3.32.2 (unaffected, semver). Source: CNA: VulnCheck

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "3.32.2",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]
```

## Severity and prioritization

- CVSS 4.0: 8.7 (high); 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; source: CNA: VulnCheck

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: VulnCheck

- CVSS 4.0: 8.7 (high); 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-122

## Exploit evidence

- exploit: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-q82v-5wjg-6h57 (disclosure@vulncheck.com)

## References

- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-q82v-5wjg-6h57 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/freerdp-before-3.32.2-heap-buffer-overflow-via-rpc-client-recv-fragment (CNA: VulnCheck; third-party-advisory)

- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-q82v-5wjg-6h57 (disclosure@vulncheck.com; Exploit, Mitigation, Vendor Advisory)

- https://www.vulncheck.com/advisories/freerdp-before-3.32.2-heap-buffer-overflow-via-rpc-client-recv-fragment (disclosure@vulncheck.com; Third Party Advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121964; retrieved 2026-11-04; source updated 2026-11-04

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-121964; retrieved 2026-11-04; source updated 2026-11-04

Revision: c179d4064b77d80c5d658813c998f47f35a5373466d27628f8f774a24a23de8b

Canonical: https://y2.dev/cve/CVE-2026-121964

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