CVE-2020-11523Public exploitNetwork attack vector

Heap overflow via wrapped rectangle dimensions

Published May 15, 2020 · Updated Aug 4, 2024

Integer overflow in FreeRDP after 1.0 through 2.0.0-rc4 allows remote authenticated users to trigger a heap overflow with bitmap dimensions. The gdi_RectToCRgn function subtracts attacker-controlled rectangle coordinates in 32-bit arithmetic, then bitmap caching multiplies the wrapped width by the pixel-format size and copies beyond a heap allocation. Reachability requires a privileged network peer to supply malformed rectangle coordinates during bitmap processing; published sources establish memory corruption but not code execution.

CVSS severity6.6
Medium
EPSS probability2.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in FreeRDP after 1.0 through 2.0.0-rc4 allows remote authenticated users to trigger a heap overflow with bitmap dimensions. The gdi_RectToCRgn function subtracts attacker-controlled rectangle coordinates in 32-bit arithmetic, then bitmap caching multiplies the wrapped width by the pixel-format size and copies beyond a heap allocation. Reachability requires a privileged network peer to supply malformed rectangle coordinates during bitmap processing; published sources establish memory corruption but not code execution.

The record

CVE
CVE-2020-11523
Published
May 15, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-190
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 15, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.6NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
6.0NIST National Vulnerability DatabaseAV:N/AC:M/Au:S/C:P/I:P/A:P

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound

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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