CVE-2026-45700Public exploitNetwork attack vector

Client heap corruption via mismatched planar decoder stride

Published May 29, 2026 · Updated May 29, 2026

Out-of-bounds write in FreeRDP before 3.26.0 allows remote attackers operating an RDP server to corrupt client-process heap memory. freerdp_bitmap_decompress_planar() checks nXDst against caller-controlled nDstStep although planar_decompress_plane_rle() writes into pTempData using the smaller nTempStep. Exploitation requires a FreeRDP client to process crafted RDPGFX planar data from a connected server; a client-process crash is confirmed, while code execution is unconfirmed.

CVSS severity7.7
High
EPSS probability4.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in FreeRDP before 3.26.0 allows remote attackers operating an RDP server to corrupt client-process heap memory. freerdp_bitmap_decompress_planar() checks nXDst against caller-controlled nDstStep although planar_decompress_plane_rle() writes into pTempData using the smaller nTempStep. Exploitation requires a FreeRDP client to process crafted RDPGFX planar data from a connected server; a client-process crash is confirmed, while code execution is unconfirmed.

The record

CVE
CVE-2026-45700
Published
May 29, 2026
Updated
May 29, 2026
Vendor
FreeRDP
Product
FreeRDP
Classifications
CWE-787, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 29, 2026CVE publishedPublication date reported by the CVE source.
  2. May 29, 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=< 3.26.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FreeRDP · FreeRDPversion=< 3.26.0

Published CVSS scores

8.8Red HatCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.7GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 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 exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1203Exploitation for Client Execution

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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