Cyber Resilience

CVE-2023-39356

Memory Safety in Freerdp ≤ 2.11.0

Public PoCMemory Safety
Published
31 August 2023
Modified
03 November 2025
Patch / advisory
View advisory
CVSS Score v3.1 5.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS Score 0.015 72th percentile
Risk Priority 47 floored blend · peak EPSS

Summary

CVE-2023-39356 is a medium-severity Out-of-bounds Read (CWE-125) vulnerability in Freerdp Freerdp. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 28% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability Data

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. In affected versions a missing offset validation may lead to an Out Of Bound Read in the function `gdi_multi_opaque_rect`. In particular there is no…

more

code to validate if the value `multi_opaque_rect->numRectangles` is less than 45. Looping through `multi_opaque_rect->`numRectangles without proper boundary checks can lead to Out-of-Bounds Read errors which will likely lead to a crash. This issue has been addressed in versions 2.11.0 and 3.0.0-beta3. Users are advised to upgrade. There are no known workarounds for this vulnerability.

CWE(s)
CWE-125

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-39353Same product: Debian Debian Linux
CVE-2023-40188Same product: Debian Debian Linux
CVE-2023-39354Same product: Debian Debian Linux
CVE-2023-40181Same product: Debian Debian Linux
CVE-2024-32459Same product: Fedoraproject Fedora
CVE-2024-32041Same product: Fedoraproject Fedora
CVE-2024-32659Same product: Fedoraproject Fedora
CVE-2024-32458Same product: Fedoraproject Fedora
CVE-2024-32658Same product: Fedoraproject Fedora
CVE-2024-32460Same product: Fedoraproject Fedora

Affected Assets

freerdp
freerdp
3.0.0 · ≤ 2.11.0
debian
debian linux
10.0
fedoraproject
fedora
37, 38, 39

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing out-of-bounds read flaws.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance includes fuzzing and static analysis that detect out-of-bounds read defects before release.

A.8.15 Logging partial match
finds

Logging can record evidence of an out-of-bounds read but does not prevent the weakness itself.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and bounds checking that directly prevent out-of-bounds reads.

A.8.26 Application security requirements partial match
prevents

Application security requirements include explicit bounds and memory-safety specifications that mitigate buffer over-reads.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles require memory-safe design patterns and runtime protections against out-of-bounds access.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe pointer arithmetic and mandate bounds-checked reads, eliminating CWE-125.

References