SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-81028

ZLMediaKit confines the downloadFile API to a configured set of root directories with a prefix comparison that does not account for directory boundaries.

MEDIUM 6.9EPSS 0.52%

Does this matter?

Lower severity and a low EPSS score (0.52%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 4.0
6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.52% probability · 44th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-22
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%26 October 2026: 0.52%26 October 202626 October 2026

EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.