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CVE-2026-44978 (GCVE-0-2026-44978)

Vulnerability from cvelistv5 – Published: 2026-07-20 16:56 – Updated: 2026-07-21 16:04
VLAI
Title
xrdp: Unchecked FIPS padding length in standard RDP Security causes heap out-of-bounds read in HMAC verification
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-21 16:03 UTC
CWE
  • CWE-20 - Improper Input Validation
  • CWE-125 - Out-of-bounds Read
Assigner
References
Impacted products
Vendor Product Version CPE status
neutrinolabs xrdp Affected: < 0.10.6.1
guessed Create a notification for this product.
Show details on NVD website
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