What’s Vulnerable › Vulnerabilities

CVE-2026-78145: CTFd __init__.py _is_safe_url redirect

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-23 · updated 2026-10-14
• Weakness: CWE-601

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.

Affected products

• CTFd: 3.8.0, 3.8.1, 3.8.2, 3.8.3, 3.8.4

References

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

Get alerted when CVE-2026-78145 or the next vulnerability affects your stack