CVE-2026-54336: JumpServer: KoKo Web Terminal SFTP Path Traversal on Authorized Asset

Vulnerability summary

CVE-2026-54336 is a medium (CVSS 5.4) vulnerability in jumpserver. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.6% of scored vulnerabilities.

Timeline

1. 17-08-2026
   PublishedVulnerability first disclosed.
2. 18-08-2026
   Last modifiedVulnerability information updated.

Description

JumpServer is an open source bastion host and an operation and maintenance security audit system. From 4.8.0 until 4.10.17, an authenticated user with SFTP permission to an authorized asset can submit crafted traversal paths through the KoKo Web Terminal SFTP feature, causing AssetDir.GetRealPath() in pkg/srvconn/sftp_asset.go to resolve paths outside the intended SFTP root and permit read, list, write, rename, or delete operations under the configured backend account on that asset. This issue is fixed in version 4.10.17.

• CWE-22Improper Limitation of a Pathname to a Restricted DirectoryThe 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.