How severe is CVE-2026-31893?

CVE-2026-31893 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-31893 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31893?

CVE-2026-31893 primarily affects Tunnelblick. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-31893?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-31893 have an EU (EUVD) identifier?

Yes. CVE-2026-31893 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27434.

When was CVE-2026-31893 published?

CVE-2026-31893 was published on 2026-05-05 and last updated on 2026-06-17.

CVE-2026-31893

CVE-2026-31893 is a medium-severity vulnerability in Tunnelblick with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-61.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v4: 6.8
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27434
Weakness: CWE-61
Affected product: Tunnelblick
Published: 2026-05-05
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-31893?: 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.
How severe is CVE-2026-31893?: CVE-2026-31893 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-31893 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31893?: CVE-2026-31893 primarily affects Tunnelblick. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-31893?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-31893 have an EU (EUVD) identifier?: Yes. CVE-2026-31893 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27434.
When was CVE-2026-31893 published?: CVE-2026-31893 was published on 2026-05-05 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:tunnelblick:tunnelblick:*:*:*:*:*:*:*:*
cpe:2.3:a:tunnelblick:tunnelblick:3.3:beta26:*:*:*:*:*:*
cpe:2.3:a:tunnelblick:tunnelblick:8.1:beta01:*:*:*:*:*:*
cpe:2.3:a:tunnelblick:tunnelblick:8.1:beta02:*:*:*:*:*:*
cpe:2.3:a:tunnelblick:tunnelblick:8.1:beta03:*:*:*:*:*:*
cpe:2.3:a:tunnelblick:tunnelblick:9.0:beta01:*:*:*:*:*:*

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