CVE-2026-27015Public exploitNetwork attack vector

Client crash via unchecked smartcard padding seek

Published Feb 25, 2026 · Updated Feb 25, 2026

Reachable assertion in FreeRDP before 3.23.0 allows remote attackers operating a malicious RDP server to crash a connected client. smartcard_unpack_read_size_align() uses Stream_Seek() for attacker-controlled NDR padding without checking that enough bytes remain, causing WINPR_ASSERT to call abort(). Smartcard redirection and verbose WINPR assertions must be enabled; the demonstrated consequence is immediate client termination without data access or code execution.

CVSS severity6.5
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in FreeRDP before 3.23.0 allows remote attackers operating a malicious RDP server to crash a connected client. smartcard_unpack_read_size_align() uses Stream_Seek() for attacker-controlled NDR padding without checking that enough bytes remain, causing WINPR_ASSERT to call abort(). Smartcard redirection and verbose WINPR assertions must be enabled; the demonstrated consequence is immediate client termination without data access or code execution.

The record

CVE
CVE-2026-27015
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
FreeRDP
Product
FreeRDP
Classifications
CWE-617, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 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=< 3.23.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FreeRDP · FreeRDPversion=< 3.23.0

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499Endpoint Denial of Service

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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