CVE-2026-81028

What it is

ZLMediaKit confines the downloadFile API to a configured set of root directories with a prefix comparison that does not account for directory boundaries. The configuration loader in server/WebApi.cpp builds each root with File::absolutePath("", item, true); because the relative-path argument is empty that helper returns the value without a trailing separator. The handler then accepts a requested path when start_with(file_path, root) holds, so a sibling directory whose name merely begins with the configured root string satisfies the test and is served. The only other guard rejects a path containing two dots, which this requires none of. The equivalent confinement check for the ordinary static file server in src/Http/HttpFileManager.cpp computes its root with a non-empty second argument, which appends the separator before comparing, and so is not affected. The endpoint requires the configured API secret, so this grants no privilege beyond what that secret already implies, but it reads files outside the directory the operator confined it to, and the reference container runs the server as root.

At a glance

Exploitability

Can be exploited over the network with an admin-level account. High risk of data exposure.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-08-26 16:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-27 11:17 UTC Last updatedMost recent change to the record

Details

Published

2026-08-26 16:16 UTC

Last modified

2026-10-27 11:17 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-22 · Path traversal

Record status

Deferred

Attack profile CVSS 4.0 · 6.9

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

High

User interaction

None

Confidentiality

High

Integrity

None

Availability

None