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Fencer Vulns
critical 9.8

CVE-2020-7245 json

Incorrect username validation in the registration process of CTFd v2.0.0 - v2.2.2 allows an attacker to take over an arbitrary account if t…

published 2020-01-23 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-28372

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.2%
EPSS 1.2% chance of exploitation in 30 days, percentile 67%
public exploits
0
none known

Summary

Incorrect username validation in the registration process of CTFd v2.0.0 - v2.2.2 allows an attacker to take over an arbitrary account if the username is known and emails are enabled on the CTFd instance. To exploit the vulnerability, one must register with a username identical to the victim's username, but with white space inserted before and/or after the username. This will register the account with the same username as the victim. After initiating a password reset for the new account, CTFd will reset the victim's account password due to the username collision.

Patch / fix

Exploit prediction

1.17% chance of exploitation in the next 30 days, higher than 67% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-640 Weak Password Recovery Mechanism for Forgotten Password

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.