CVE-2023-36053
Djangoproject Django 3.2 – 3.2.20
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSummary
CVE-2023-36053 is a high-severity Inefficient Regular Expression Complexity (CWE-1333) vulnerability in Djangoproject Django. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked in the top 14% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2023-36053 affects Django versions 3.2 before 3.2.20, 4 before 4.1.10, and 4.2 before 4.2.3. The flaw resides in the EmailValidator and URLValidator classes, which rely on regular expressions that can be forced into catastrophic backtracking when presented with input containing an extremely large number of domain-name labels.
An unauthenticated remote attacker can supply a maliciously crafted email address or URL containing thousands of labels in the domain portion. Because the vulnerable validators perform no length or complexity checks before matching, processing such input consumes excessive CPU time and can render the validating application unresponsive, achieving a denial-of-service condition without any authentication or user interaction.
Official Django security advisories and downstream distribution notices direct users to upgrade immediately to 3.2.20, 4.1.10, or 4.2.3 or later; these releases contain revised validators that limit label count and avoid the expensive regex path. The associated EPSS score has remained essentially flat near 0.1 since disclosure, indicating limited observed exploitation interest to date.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-0065
Vulnerability Data
In Django 3.2 before 3.2.20, 4 before 4.1.10, and 4.2 before 4.2.3, EmailValidator and URLValidator are subject to a potential ReDoS (regular expression denial of service) attack via a very large number of domain name labels of emails and URLs.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect and reject regex patterns with exponential worst-case complexity.
Secure development lifecycle mandates review of algorithmic efficiency, directly addressing ReDoS-prone regex.
Application security requirements can specify input-validation rules that limit regex complexity.
Secure architecture principles encourage avoidance of computationally expensive constructs such as catastrophic backtracking.
Secure coding standards explicitly prohibit or limit the use of inefficient regular expressions.