CVE-2026-42275 is a high-severity (CVSS 8.7) Path Traversal vulnerability in github.com/openziti/zrok. A fix is available for github.com/openziti/zrok — see the affected versions and patch details below.
zrok: WebDAV drive backend follows symlinks outside DriveRoot, enabling host filesystem read/write
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42275.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/openziti/zrok🐹github.com/openziti/zrok/v2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary 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.
- Attack Vector: Network — exploitation is performed entirely over the WebDAV endpoint; the attacker issues HTTP requests to the public zrok share URL.
- Attack Complexity: High — a precondition outside the attacker's direct control must hold: a symlink pointing outside DriveRoot must already exist within it (created locally, not via WebDAV).
- Privileges Required: None — zrok share public --backend-mode drive exposes the WebDAV endpoint with no authentication by default.
- User Interaction: None — once the symlink precondition is met, exploitation requires no user interaction.
- Scope: Changed — the vulnerability allows an attacker to escape the WebDAV root (the security boundary) and access the broader host filesystem.
- Confidentiality Impact: High — arbitrary files readable by the zrok process can be retrieved.
- Integrity Impact: High — the WebDAV PUT handler opens files with O_RDWR|O_CREATE|O_TRUNC, meaning symlink targets outside DriveRoot can be overwritten (e.g. ~/.ssh/authorized_keys).
- Availability Impact: None — no direct availability impact.
Affected Components
- drives/davServer/file.go — Dir.OpenFile (line 140), Dir.Stat (line 176), Dir.Mkdir (line 133), Dir.RemoveAll (line 151)
- endpoints/drive/backend.go — NewBackend (line 51–52)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/openziti/zrok | all versions | No fix |
| 🐹Go | github.com/openziti/zrok/v2 | all versions | 2.0.2go get github.com/openziti/zrok/v2@v2.0.2 |
Affected Products
zroknetfoundryDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/openziti/zrok, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
A fix is available for CVE-2026-42275; check the affected-versions list above or the advisory for the patched release of github.com/openziti/zrok, then make sure no transitive dependency still pins the vulnerable range.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is CVE-2026-42275 in your dependencies?
Find it across Go, including transitive dependencies.