CVE-2021-45115
Status: ModifiedHigh (7.5)—
An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 2.42%
- Percentile among all scored CVEs: 84
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- NVD-CWE-Other
References
- https://docs.djangoproject.com/en/4.0/releases/security/
- https://groups.google.com/forum/#%21forum/django-announce
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV/
- https://security.netapp.com/advisory/ntap-20220121-0005/
- https://www.djangoproject.com/weblog/2022/jan/04/security-releases/
- https://docs.djangoproject.com/en/4.0/releases/security/
- https://groups.google.com/forum/#%21forum/django-announce
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B4SQG2EAF4WCI2SLRL6XRDJ3RPK3ZRDV/
- https://security.netapp.com/advisory/ntap-20220121-0005/
- https://www.djangoproject.com/weblog/2022/jan/04/security-releases/
Raw JSON (NVD)
Show
{
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"vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "NONE"
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"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
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"published": "2022-01-05T00:15:07.907",
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},
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}
],
"lastModified": "2026-06-17T04:13:11.547",
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