CVE-2026-78145

Medium

Description

A vulnerability has been found in CTFd up to 3.8.4. The affected element is the function _is_safe_url of the file CTFd/utils/validators/__init__.py. Such manipulation of the argument Next leads to open redirect. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The name of the patch is 5d8515842fd1ab2c3a9f2dde9ffca907aa334ea9. Upgrading the affected component is recommended.

SeverityMedium

CVSS4.3

Exploit probability—

ProductCtfd

PublishedAug 23, 2026

First seenAug 23, 2026

Weakness typeCWE-601Open redirect

How to fix

Patches

github.com/CTFd/CTFd/pull/3026
github.com/CTFd/CTFd/commit/5d8515842fd1ab2c3a9f2dde9ffca907aa334ea9
github.com/CTFd/CTFd/releases/tag/3.8.4

Affected products

Product	Affected versions	Fixed in
ctfd ctfd	3.8.0, 3.8.1, 3.8.2, 3.8.3, 3.8.4	—

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