CVE-2026-110766

Deferred Deferred - Pending Action

Colanode Server Path Traversal via AvatarId Parameter

Publication date: 2026-10-14

Last updated on: 2026-10-14

Assigner: VulnCheck

Description

Colanode server through 0.4.7 contains a path traversal vulnerability that allows authenticated users to read arbitrary .jpeg files by supplying an encoded traversal sequence in avatarId. Attackers can send percent-encoded ../ sequences to GET /client/v1/avatars/:avatarId to escape the avatars directory and read .jpeg files belonging to other workspaces.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-10-14

Last Modified

2026-10-14

Generated

2026-10-19

AI Q&A

2026-10-15

EPSS Evaluated

2026-10-18

NVD

CVE-2026-110766

EUVD

EUVD-2026-101566

Affected Vendors & Products

Vendor	Product	Version / Range
colanode	colanode	0

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-22	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.

Attack-Flow Graph

Executive Summary

This is a path traversal vulnerability in Colanode server versions up to 0.4.7. Authenticated users can read arbitrary .jpeg files by sending percent-encoded ../ sequences in the avatarId parameter. The server constructs a file path using avatarId as avatars/${avatarId}.jpeg without proper validation, allowing attackers to escape the avatars directory and access files from other workspaces.

Detection Guidance

To detect this vulnerability, check Colanode server logs for requests to GET /client/v1/avatars/:avatarId with percent-encoded traversal sequences like ..%2f or ..%252f in the avatarId parameter. Use tools like curl to test if arbitrary .jpeg files can be accessed by sending crafted requests to the avatar download endpoint.

Example command: curl -v 'http://<server>/client/v1/avatars/..%2f..%2f..%2fetc%2fpasswd.jpeg' to test for path traversal. If the server responds with file contents instead of an error, the vulnerability is likely present.

Impact Analysis

An attacker with valid credentials could access sensitive images stored on the server, potentially exposing confidential workspace data, user avatars, or other protected files. This could lead to privacy violations, data leaks, or unauthorized information disclosure depending on the files accessed.

Compliance Impact

This vulnerability could violate data protection requirements under GDPR (unauthorized access to personal data) and HIPAA (exposure of protected health information). Organizations using affected Colanode versions may face compliance violations, legal penalties, and reputational damage if sensitive data is compromised through this flaw.

Mitigation Strategies

Immediately update Colanode server to the latest version beyond 0.4.7. If an update is not available, restrict access to the /client/v1/avatars/:avatarId endpoint to trusted users only. Implement strict input validation for the avatarId parameter to ensure it only contains expected characters (e.g., 28-character base32 string).

Add path containment checks in the storage backend to prevent traversal sequences from escaping the avatars directory. Monitor server logs for suspicious requests attempting to access unauthorized files.

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