CVE-2020-4031Network attack vector

Client crash via freed object reuse

Published Jun 22, 2020 · Updated Aug 4, 2024

Use-after-free in FreeRDP before 2.1.2 allows remote attackers to crash compatible clients using /relax-order-checks. The advisory identifies gdi_SelectObject but does not disclose which object is freed or how subsequent processing reuses it. Only compatibility-mode clients launched with /relax-order-checks are affected, and the published consequence is a double-free crash.

CVSS severity7.5
High
EPSS probability1.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in FreeRDP before 2.1.2 allows remote attackers to crash compatible clients using /relax-order-checks. The advisory identifies gdi_SelectObject but does not disclose which object is freed or how subsequent processing reuses it. Only compatibility-mode clients launched with /relax-order-checks are affected, and the published consequence is a double-free crash.

The record

CVE
CVE-2020-4031
Published
Jun 22, 2020
Updated
Aug 4, 2024
Vendor
FreeRDP
Product
FreeRDP
Classifications
CWE-416, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 22, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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=< 2.1.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FreeRDP · FreeRDPversion=< 2.1.2

Published CVSS scores

4.3NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
3.5GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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