LabOne: Improper Limitation of a Pathname to a Restricted Directory
CVE-2026-6903 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in LabOne from Zurich Instruments, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 26.01.3.9 as the first without the flaw, so updating LabOne to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update LabOne to 26.01.3.9 or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Zurich Instruments | LabOne | before 26.01.3.9 | 26.01.3.9 |
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
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CNA (ncsc.ch).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (ncsc.ch) |
| CVSS 3.1 | 7.5 | High | CNA (ncsc.ch) |
Official description
The LabOne Web Server, backing the LabOne User Interface, contains insufficient input validation in its file access functionality. An unauthenticated attacker could exploit this vulnerability to read arbitrary files on the host system that are accessible to the operating system user running the LabOne software. Additionally, the Web Server does not sufficiently restrict cross-origin requests, which could allow a remote attacker to trigger file access from a victim's browser by directing the victim to a malicious website. The vulnerability is only exploitable when the LabOne Web Server is running. Installations using only the LabOne APIs without starting the Web Server are not exposed.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 7.8 High severity
- 7.1 High severity
- 7.5 High severity
- 10.0 Critical severity
- 7.5 High severity
- 8.7 High severity
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