CyberSecBulletin
CVE-2023-4760NVD status: Modified

Eclipse RAP: Improper Limitation of a Pathname to a Restricted Directory

Published Updated By the CyberSecBulletin desk

CVE-2023-4760 is a critical-severity improper limitation of a pathname to a restricted directory vulnerability in Eclipse RAP from Eclipse Foundation, 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 Eclipse RAP versions: 3.0.0 through 3.25.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.25% chance of exploitation within 30 days, higher than 70% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Eclipse RAP you run against the affected versions below, and install the vendor's latest release.
  2. 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
Eclipse FoundationEclipse RAP3.0.0 through 3.25.0Not stated
EclipseRemote Application Platform3.0.0 through 3.25.0Not 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 3.17.6HighCNA (eclipse.org)
CVSS 3.19.8CriticalNVD

Official description

In Eclipse RAP versions from 3.0.0 up to and including 3.25.0, Remote Code Execution is possible on Windows when using the FileUpload component. The reason for this is a not completely secure extraction of the file name in the FileUploadProcessor.stripFileName(String name) method. As soon as this finds a / in the path, everything before it is removed, but potentially \ (backslashes) coming further back are kept. For example, a file name such as /..\..\webapps\shell.war can be used to upload a file to a Tomcat server under Windows, which is then saved as ..\..\webapps\shell.war in its webapps directory and can then be executed.

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

The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)

Timeline

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

References

Patches and release notes

Technical write-ups (may include proof of concept)

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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