CyberSecBulletin
CVE-2022-24883NVD status: Modified

FreeRDP: Improper Authentication

Published Updated By the CyberSecBulletin desk

CVE-2022-24883 is a critical-severity improper authentication vulnerability in FreeRDP, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected FreeRDP versions: < 2.7.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.34% chance of exploitation within 30 days, higher than 84% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of FreeRDP you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
FreeRDPFreeRDP< 2.7.0Not stated
Fedora ProjectFedora34; 35; 36Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.4HighCNA (github.com)
CVSS 3.19.8CriticalNVD
CVSS 2.06.8MediumNVD

Official description

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP). Prior to version 2.7.0, server side authentication against a `SAM` file might be successful for invalid credentials if the server has configured an invalid `SAM` file path. FreeRDP based clients are not affected. RDP server implementations using FreeRDP to authenticate against a `SAM` file are affected. Version 2.7.0 contains a fix for this issue. As a workaround, use custom authentication via `HashCallback` and/or ensure the `SAM` database path configured is valid and the application has file handles left.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in FreeRDP

All FreeRDP vulnerabilities

Recent Improper Authentication vulnerabilities

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