Internationalized Domain Names in Applications (IDNA) for Python provides support for Internationalized Domain Names in Applications (IDNA) and Unicode IDNA Compatibility Processing. In versions prior to 3.15, payloads such as `"\u0660" * N` or `"\u30fb" * N + "\u6f22"` utilize the `valid_contexto` function prior to length rejection, and for high values of `N` will take a long time to process. This is the same issue as CVE-2024-3651, however the original remediation in 2024 was not a complete fix. A specially crafted argument to the `idna.encode()` function could consume significant resources. This may lead to a denial-of-service. Starting in version 3.14, the function rejects long inputs as soon as practicable prior to any further processing to minimize resource consumption. In version 3.15, this approach was extended to lesser used alternate functions (i.e. per-label conversions and codec support). A workaround is available. Domain names cannot exceed 253 characters in length. If this length limit is enforced prior to passing the domain to the `idna.encode()` function, it should no longer consume significant resources. This is triggered by arbitrarily large inputs that would not occur in normal usage, but may be passed to the library assuming there is no preliminary input validation by the higher-level application.
References
| Link | Resource |
|---|---|
| https://github.com/kjd/idna/security/advisories/GHSA-65pc-fj4g-8rjx | Mitigation Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
23 Jul 2026, 07:10
| Type | Values Removed | Values Added |
|---|---|---|
| Summary |
|
15 Jun 2026, 18:52
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:kjd:internationalized_domain_names_in_applications:*:*:*:*:*:python:*:* | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.3 |
| First Time |
Kjd internationalized Domain Names In Applications
Kjd |
|
| References | () https://github.com/kjd/idna/security/advisories/GHSA-65pc-fj4g-8rjx - Mitigation, Vendor Advisory |
05 Jun 2026, 23:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-06-05 23:16
Updated : 2026-07-23 07:10
NVD link : CVE-2026-45409
Mitre link : CVE-2026-45409
CVE.ORG link : CVE-2026-45409
JSON object : View
Products Affected
kjd
- internationalized_domain_names_in_applications
CWE
CWE-1333
Inefficient Regular Expression Complexity
