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Fencer Vulns
high 7.7

CVE-2024-24771 json

Open Forms potential multi-factor authentication bypass

published 2024-02-07 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-22154

cvss
7.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

Summary

Open Forms allows users create and publish smart forms. Versions prior to 2.2.9, 2.3.7, 2.4.5, and 2.5.2 contain a non-exploitable multi-factor authentication weakness. Superusers who have their credentials (username + password) compromised could potentially have the second-factor authentication bypassed if an attacker somehow managed to authenticate to Open Forms. The maintainers of Open Forms do not believe it is or has been possible to perform this login. However, if this were possible, the victim's account may be abused to view (potentially sensitive) submission data or have been used to impersonate other staff accounts to view and/or modify data. Three mitigating factors to help prevent exploitation include: the usual login page (at `/admin/login/`) does not fully log in the user until the second factor was succesfully provided; the additional non-MFA protected login page at `/api/v2/api-authlogin/` was misconfigured and could not be used to log in; and there are no additional ways to log in. This also requires credentials of a superuser to be compromised to be exploitable. Versions 2.2.9, 2.3.7, 2.4.5, and 2.5.2 contain the following patches to address these weaknesses: Move and only enable the API auth endpoints (`/api/v2/api-auth/login/`) with `settings.DEBUG = True`. `settings.DEBUG = True` is insecure and should never be applied in production settings. Additionally, apply a custom permission check to the hijack flow to only allow second-factor-verified superusers to perform user hijacking.

Patch / fix

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.60% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.7 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N

Affected products

  • open-formulieren open-forms

Classification

Weakness
  • CWE-284 Improper Access Control
  • CWE-287 Improper Authentication
  • CWE-654 Reliance on a Single Factor in a Security Decision

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.