CyberSecBulletin
CVE-2026-73509NVD status: Deferred

OpenList: Improper Limitation of a Pathname to a Restricted Directory

CVE-2026-73509 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in OpenList from OpenListTeam, with a CVSS 3.1 base score of 7.6 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected OpenList versions: < 4.2.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.52% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of OpenList 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.

Affected products and versions

VendorProductAffected versionsFixed in
OpenListTeamOpenList< 4.2.4Not 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
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
LowSome restricted data can be read.
Integrity
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L. Scored by CNA (github.com).

Official description

OpenList a file list program that supports multiple storage. Prior to 4.2.4, the authenticated /api/fs/batch_rename handler in server/handles/fsbatch.go authorizes only the source directory produced by user.JoinPath(req.SrcDir) and validates renameObject.NewName with checkRelativePath, but does not validate attacker-controlled renameObject.SrcName, supplied as src_name, before concatenating it with the authorized path and passing the result to fs.Rename. A user with rename permission can use traversal segments in src_name to make path normalization select a file outside the authorized directory and configured base path, resulting in cross-user file integrity loss, limited availability impact, and file-existence disclosure through success or error responses. This issue is fixed in version 4.2.4.

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: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in OpenList

All OpenList vulnerabilities

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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