CVE-2026-63652Public exploitNetwork attack vector

Service crash via malformed rdpsnd formats double-free

Published Aug 19, 2026 · Updated Aug 19, 2026

Double free in FreeRDP before 3.28.0 allows remote authenticated users to crash the rdpsnd server channel via a malformed Client Audio Formats PDU. rdpsnd_server_recv_formats() allocates context->client_formats, frees it on per-record validation errors such as an oversized cbSize, and leaves both the pointer and num_client_formats unchanged for later teardown. The bug is reachable only after an RDP handshake by an authenticated client, and the second free in rdpsnd_server_context_free() yields reliable process termination with allocator-dependent heap corruption beyond the crash.

CVSS severity7.1
High
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Double free in FreeRDP before 3.28.0 allows remote authenticated users to crash the rdpsnd server channel via a malformed Client Audio Formats PDU. rdpsnd_server_recv_formats() allocates context->client_formats, frees it on per-record validation errors such as an oversized cbSize, and leaves both the pointer and num_client_formats unchanged for later teardown. The bug is reachable only after an RDP handshake by an authenticated client, and the second free in rdpsnd_server_context_free() yields reliable process termination with allocator-dependent heap corruption beyond the crash.

The record

CVE
CVE-2026-63652
Published
Aug 19, 2026
Updated
Aug 19, 2026
Vendor
FreeRDP
Product
FreeRDP
Classifications
CWE-415, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.28.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

FreeRDP · FreeRDPversion=< 3.28.0

Published CVSS scores

7.1GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-415Double Free
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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