CVE-2026-42275 | zrok: WebDAV drive backend follows symlinks outside DriveRoot, enabling host filesystem read/write

zrok is software for sharing web services, files, and network resources. Prior to version 2.0.2, the zrok WebDAV drive backend (davServer.Dir) restricts path traversal through lexical normalization but does not prevent symlink following. When a symbolic link inside the shared DriveRoot points to a location outside that root, remote WebDAV consumers can read files and—on shares without OS-level permission restrictions—write or overwrite files anywhere on the host filesystem accessible to the zrok process. This issue has been patched in version 2.0.2.

Published: 2026-05-08 Last update: 2026-05-08 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-42275 is rated Moderate Risk (40.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-42275

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-14 0.04% 0.05% +0.02%
2 2026-05-08 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-42275

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.7 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 5.8 [email protected]

Weakness enumeration for CVE-2026-42275

GitHub Security Advisory for CVE-2026-42275

GHSA-74m3-9qvm-rp9h · Severity: high · Ecosystem: go — zrok: WebDAV drive backend follows symlinks outside DriveRoot, enabling host filesystem read/write

Affected software / configurations for CVE-2026-42275

Vendor Product Version Raw CPE
netfoundry zrok < 2.0.2 cpe:2.3:a:netfoundry:zrok:*:*:*:*:*:*:*:*

References for CVE-2026-42275

cvelogic Threat Intelligence