Client heap corruption via inverted overflow guard
Published Jul 10, 2026 · Updated Jul 10, 2026
Heap-based buffer overflow in 32-bit FreeRDP clients before 3.28.0 allows remote attackers to corrupt heap memory via crafted RDP delta points. update_read_delta_points in libfreerdp/core/orders.c applies an inverted overflow guard, then multiplies the untrusted point count for realloc and ZeroMemory. Reachability requires a 32-bit client to process delta-point orders from a malicious RDP peer; exploitation can crash the client or enable code execution depending on heap layout.
Summary
What happened
Heap-based buffer overflow in 32-bit FreeRDP clients before 3.28.0 allows remote attackers to corrupt heap memory via crafted RDP delta points. update_read_delta_points in libfreerdp/core/orders.c applies an inverted overflow guard, then multiplies the untrusted point count for realloc and ZeroMemory. Reachability requires a 32-bit client to process delta-point orders from a malicious RDP peer; exploitation can crash the client or enable code execution depending on heap layout.
The record
- CVE
- CVE-2026-57156
- Published
- Jul 10, 2026
- Updated
- Jul 10, 2026
- Vendor
- FreeRDP
- Product
- FreeRDP
- Classifications
- CWE-190, CWE-122, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 10, 2026CVE publishedPublication date reported by the CVE source.
- Jul 10, 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.
- Affected versionversion=< 3.28.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- GHSA-v5wf-j8j4-77h7 proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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