Is CVE-2026-33868 actively exploited?

No active exploitation of CVE-2026-33868 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-33868 be exploited remotely?

Yes. CVE-2026-33868 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-33868?

CVE-2026-33868 has a CVSS score of 6.1 (MEDIUM).

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MEDIUM

CVE-2026-33868

CWE-601Published: March 27, 2026· Updated: Mar 30, 2026

6.1

CVSS v3.1

EPSS:0.86%probability of exploitation in 30 daysPercentile:75.0th

Official Description

Mastodon is a free, open-source social network server based on ActivityPub. Prior to versions 4.5.8, 4.4.15, and 4.3.21, an unauthenticated Open Redirect vulnerability (CWE-601) exists in the `/web/*` route due to improper handling of URL-encoded path segments. An attacker can craft a specially encoded URL that causes the application to redirect users to an arbitrary external domain, enabling phishing attacks and potential OAuth credential theft. The issue occurs because URL-encoded slashes (`%2F`) bypass Rails path normalization and are interpreted as host-relative redirects. Versions 4.5.8, 4.4.15, and 4.3.21 patch the issue.

NVD Source

Technical Analysis

CVE-2026-33868 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.