Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessReach exposed FreeRDP proxy over network
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DeliveryOpen session and RDPDR channel
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ExploitSend FIRST fragment without LAST
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ExecutionStream continuation fragments indefinitely
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PersistUnbounded heap stream growth per session
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ImpactProxy memory exhausted, service denied
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource consumption limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires the target to be running FreeRDP in PROXY mode (the pf/proxy component) with the RDPDR device-redirection channel reachable by the attacker - plain FreeRDP client or server deployments are not the stated target. The attacker sends a FIRST RDPDR fragment followed by continuation fragments that never carry the LAST flag, and must SUSTAIN this traffic because memory growth is proportional to bytes sent (reflected in AC:H/AT:P); a single packet does not trigger the condition. No authentication is required (PR:N) and no user interaction is needed (UI:N). Limiting factors: only affected versions 3.0.0-beta1 through before 3.32.0 are vulnerable, the proxy must be exposed to untrusted clients, and the gradual exhaustion depends on the attacker maintaining the fragment stream long enough to outpace available memory. |
| Impact | This is a memory-exhaustion denial-of-service (CWE-400) in the FreeRDP proxy, rated CVSS 4.0 8.2 (High). The vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N with VC:N/VI:N/VA:H confirms a network-reachable, unauthenticated (PR:N) attack that affects availability ONLY - there is no confidentiality or integrity impact, so this cannot lead to code execution or data theft. The elevated AC:H and AT:P (attack requirements present) are meaningful: the attacker must sustain a stream of RDPDR continuation fragments and the impact grows proportional to traffic, so exhaustion is gradual rather than a single-packet crash. No EPSS score, CISA KEV listing, or public POC is present in the provided data, so there is no evidence of active exploitation or weaponization - this is 'no public exploit identified at time of analysis.' Net assessment: a credible availability risk for anyone running FreeRDP in proxy mode exposed to untrusted clients, but it is a resource-exhaustion DoS rather than a critical RCE; the raw 8.2 overstates urgency relative to the single-dimension (availability-only) impact. Note the tension between AV:N/PR:N (sounds trivially remote) and AC:H/AT:P plus the gradual proportional-growth mechanism, which together imply exploitation requires sustained effort against a specifically-deployed proxy rather than a one-shot remote kill. |
| Exploit ScenarioDerived | An attacker who can reach a FreeRDP proxy opens a session and sends a FIRST RDPDR channel fragment followed by an unbounded stream of continuation fragments that never include a LAST marker. Because no cumulative or absolute size limit is enforced during reassembly, the per-session heap stream grows in proportion to the traffic sent, eventually exhausting proxy memory and denying service to legitimate users. No public exploit code was identified; the attack is unauthenticated (PR:N) but requires sustained traffic (AC:H/AT:P) rather than a single crafted packet. |
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Alert meAnalysisAIv1 – Oct 14, 2026
Unbounded heap accumulation in the FreeRDP proxy (the pf/proxy relay component) lets unauthenticated remote attackers exhaust proxy memory by streaming RDPDR device-redirection fragments that begin with a FIRST fragment but never carry a LAST fragment, so reassembly state grows in proportion to bytes sent. Affected deployments are FreeRDP 3.0.0-beta1 through versions before 3.32.0 that run the proxy with the RDPDR channel reachable from untrusted clients; plain FreeRDP client or server deployments are not the stated target. Rated CVSS 4.0 8.2 (High), with assessed CVSS 3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H, this is a slow-burn memory-exhaustion DoS requiring sustained fragment traffic rather than a single packet, and there is no public exploit identified at time of analysis.
RemediationAI
The version boundary in the advisory (affected: 3.0.0-beta1 before 3.32.0) indicates the fix is contained in FreeRDP 3.32.0, so upgrading the proxy to 3.32.0 or later is the primary remediation; consult GHSA-m7g5-gw57-cwcr and the VulnCheck advisory for the vendor's confirmation and the exact release notes. If upgrading immediately is not possible, the most effective compensating control is to remove the attack surface: do not run the FreeRDP proxy in PROXY mode exposed to untrusted clients, and do not enable RDPDR device redirection (drive, printer, port, smartcard) on the proxy side, since without a negotiated RDPDR channel there is no fragment stream to accumulate - the trade-off is loss of redirected device functionality for legitimate users. Where device redirection is genuinely required, place the proxy behind authentication and network access controls so only vetted clients can reach it, and cap the proxy process with cgroup/systemd memory limits (MemoryMax) plus a restart policy so that runaway per-session heap growth kills or recycles the proxy instead of exhausting host memory - this converts a host-wide outage into a bounded, monitored session failure and is a trade-off that will drop in-flight sessions once the limit is hit. Additionally, configure an inactivity/partial-message timeout that drops sessions which have not sent a valid terminating fragment within a short window, and monitor per-session heap growth to detect the FIRST-without-LAST pattern early; both add latency tolerance risk for slow or heavily fragmented legitimate RDPDR traffic. No official workaround patch is described in the provided references, so mitigation by upgrade remains the recommended path.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
RDPDR is the Remote Desktop Protocol static virtual channel that carries device redirection (drives, printers, ports) between an RDP client and server. The FreeRDP proxy (pf/proxy) terminates an inbound client connection and re-originates it toward the downstream target, which means it must reassemble inbound RDPDR channel data split across fragments delimited by FIRST and LAST flags before relaying it. This advisory concerns the reassembly buffer for that channel: affected builds enforce neither a cumulative nor an absolute size cap on the per-session heap stream, which maps to CWE-400 (Uncontrolled Resource Consumption). An attacker who can reach the proxy's RDPDR channel sends a FIRST fragment followed by an endless series of continuation fragments, each of which is accepted and appended to the per-session stream, so heap growth is directly proportional to attacker-supplied traffic. The attack is gradual by nature, which is reflected in the CVSS vectors through AC:H and AT:P (attack complexity high, attack requirements present) - memory must be outgrown over a sustained period, the proxy must be exposed to untrusted clients, and the RDPDR channel must be reachable; authentication and user interaction are not required (PR:N, UI:N) per the assessed vector. Only availability is impacted (VA:H); confidentiality and integrity are unaffected, and the flaw does not cross a trust boundary beyond the proxy process itself (S:U).
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Severity by source
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Network-reachable and unauthenticated (AV:N/PR:N); AC:H because exhaustion needs sustained proportional traffic, not one packet; availability-only impact (A:H, C/I:N), no scope change.
Primary rating from Vendor (vulncheck).
CVSS VectorVendor: vulncheck
Lifecycle Timeline
2DescriptionCVE.org
FreeRDP from 3.0.0-beta1 before 3.32.0 fails to enforce cumulative or absolute size limits when reassembling RDPDR channel fragments in the proxy. Attackers can send a FIRST fragment followed by continuation fragments without LAST, growing per-session heap streams proportional to traffic and exhausting proxy memory.
Technical POC Analysis
Note on identifiers: the supplied advisory is GHSA-m7g5-gw57-cwcr, rated Moderate 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H) and marked "No known CVE" at time of publication.
Full technical POC analysis - root cause, step-by-step exploitation and patch breakdown - is part of the Pro and Business plans.
Executive ViewAI
A high-severity flaw in the FreeRDP proxy component lets unauthenticated network clients gradually exhaust memory on any proxy instance that exposes the RDPDR device-redirection channel to untrusted traffic, degrading or halting remote desktop sessions for everyone routed through it. The attack requires no credentials and no public exploit code has been identified, so the primary risk is availability of the proxy tier rather than data exposure or compromise. Leadership should care because these proxies typically sit at the edge enabling contractors, remote staff, and third parties to reach internal systems, so sustained memory exhaustion there can interrupt those access paths across the organization.
No vendor-released patch identified at time of analysis. Interim mitigations: disable or restrict the RDPDR channel on any proxy instance reachable from untrusted clients; segment the proxy so RDPDR traffic is limited to trusted source ranges; enforce hard memory ceilings via container/cgroup limits with automatic restart; apply per-connection and per-source rate limiting on the relay listener; and monitor for first-fragment-only RDPDR fragment streams and growing reassembly memory to detect abuse early.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Use-after-free in FreeRDP xf_clipboard_format_equal before 3.23.0. Clipboard format comparison uses freed memory. Fifth
Use-after-free in FreeRDP xf_AppUpdateWindowFromSurface before 3.23.0. Surface-to-window update triggers memory corrupti
Use-after-free in FreeRDP xf_SetWindowMinMaxInfo before version 3.23.0. X11 client window management triggers memory cor
Use-after-free in FreeRDP xf_cliprdr_provide_data clipboard handling before 3.23.0. Clipboard data exchange triggers mem
FreeRDP IRP thread handler has a use-after-free where the IRP is freed by Complete() then accessed on the error path. Fi
FreeRDP drive read heap overflow when server-controlled read length exceeds IRP output buffer. Fixed in 3.20.1. PoC avai
FreeRDP client before 3.20.1 has a heap buffer overflow in AUDIN format processing. A malicious RDP server can corrupt m
Use-after-free in FreeRDP xf_AppUpdateWindowFromSurface before 3.23.0. Different code path from CVE-2026-25953. PoC and
FreeRDP is a free implementation of the Remote Desktop Protocol. Rated critical severity (CVSS 9.8), this vulnerability
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical
EUVD-2026-101716
GHSA-qh7g-q627-6q97
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB