CVE-2026-31893 (GCVE-0-2026-31893)
Vulnerability from cvelistv5 – Published: 2026-05-05 18:55 – Updated: 2026-05-05 19:37
VLAI?
Title
Tunnelblick arbitrary file read via symlink following in tunnelblickd
Summary
Tunnelblick is an open source graphic user interface for OpenVPN on macOS. In versions 3.3beta26 through 9.0beta01, any local user can read arbitrary root-owned files by exploiting a symlink following vulnerability in tunnelblick-helper, reachable through the world-accessible tunnelblickd Unix socket. The socket is configured with mode 0666, allowing any local user to connect. No authorization check is performed on the connecting client. The tunnelblick-helper process constructs a path to config.ovpn inside a user-controlled .tblk directory and reads it as root without symlink validation. An attacker can create a .tblk configuration with a symlinked config.ovpn pointing to any file and request tunnelblickd to read it. This issue has been fixed in versions 9.0beta02.
Severity ?
CWE
- CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Tunnelblick | Tunnelblick |
Affected:
>= 3.3beta26, < 9.0beta02
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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