CVE Tools

CVE-2026-44978

xrdp: Unchecked FIPS padding length in standard RDP Security causes heap out-of-bounds read in HMAC verification

No known exploitation. EPSS puts it in the 42nd percentile. A vendor fix is available.

Published Updated Sources: CVE.org, NVD

What to do

The vendor has published a fix. Version details are below where the sources state them.

What it is

From the CVE record

xrdp is an open source RDP server. Versions 0.10.6 and prior contain a heap out-of-bounds read vulnerability within the FIPS-specific receive paths. This vulnerability does not affect the default configuration of xrdp. The vulnerability is only exploitable when the security layer is set to security_layer=negotiate or security_layer=rdp, and the crypto level is changed to crypt_level=fips in xrdp.ini. In this specific non-default mode, the server fails to validate the FIPS padding length field, leading to a pointer underflow and a subsequent negative length calculation. An unauthenticated remote attacker can exploit this by sending a crafted FIPS-protected PDU, causing a heap out-of-bounds read that results in a process crash and denial of service (DoS). However, since xrdp forks a new process for each connection by default, an out-of-bounds read causing a process crash is unlikely to bring down the entire xrdp service. This issue has been fixed in version 0.10.6.1.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS42nd
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.5% chance of exploitation activity in the next 30 days, which ranks it in the 42nd percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

8 events over 5 days, from the signal feeds we watch.

  1. Patch availablerecord updated
  2. Record updated
  3. Publishedweakness classified, att&ck mapped, record updated
  4. OpenVAS check added

Affected products

Technical detail

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Scored 5.3 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality NoneNo confidentiality impact
  • Integrity NoneNo integrity impact
  • Availability LowReduced performance or intermittent disruption of service

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

Watch the software you run.

My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.

We'll flag the next CVE, public exploit or patch for Xrdp, not every advisory.

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