CVE-2026-78145

MEDIUM 4.3

CTFd init.py _is_safe_url redirect

CVSS Score

4.3

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-601
Vendor	n/a
Product	ctfd
Published	Aug 23, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Scope

Confidentiality

Integrity

Availability

Affected Versions

n/a / CTFd

3.8.0 3.8.1 3.8.2 3.8.3 3.8.4

References

NVD ↗ CVE.org ↗ EPSS Data ↗

vuldb.com: https://vuldb.com/vuln/394533 vuldb.com: https://vuldb.com/vuln/394533/cti vuldb.com: https://vuldb.com/cve/CVE-2026-78145 vuldb.com: https://vuldb.com/submit/882469 mblunt.dev: https://mblunt.dev/writeups/ctfd-open-redirect/ github.com: https://github.com/CTFd/CTFd/pull/3026 github.com: https://github.com/CTFd/CTFd/commit/5d8515842fd1ab2c3a9f2dde9ffca907aa334ea9 github.com: https://github.com/CTFd/CTFd/releases/tag/3.8.4 github.com: https://github.com/CTFd/CTFd/

Credits

🔍 mblunt (VulDB User)