CWE · MITRE source
CWE-939Improper Authorization in Handler for Custom URL Scheme
The product uses a handler for a custom URL scheme, but it does not properly restrict which actors can invoke the handler using the scheme.
Mobile platforms and other architectures allow the use of custom URL schemes to facilitate communication between applications. In the case of iOS, this is the only method to do inter-application communication. The implementation is at the developer's discretion which may open security flaws in the application. An example could be potentially dangerous functionality such as modifying files through a custom URL scheme.
Last updated: 15 October 2026 20:36 UTC
Control responseHuman-reviewed
Answering this weakness across the control lifecycle, from our framework cross-walks.
NIST 800-53 r5 controls PROPOSED for this weakness (0)AI-assisted
These are model PROPOSALS, not graded mappings. They come
from controls_to_cwe_proposals, which carries no grade field at
all; across the CWE pages 1,540 of 1,722 such associations (89%) have never
been graded by anything. The heading said “address” until
2026-09-29, which asserted a relationship the data does not carry.
Graded cross-walks are on the framework map, not here.
| Control | Title | Family | Why it addresses this CWE |
|---|---|---|---|
| No NIST controls proposed yet. | |||
Top CVEs of this weakness type, ranked by Risk Priority
| CVE | Risk | CVSS | EPSS | Published |
|---|---|---|---|---|
CVE-2024-33606 UPD | 6.6 | 8.8 | 0.0046 | 2024-06-11 |
CVE-2026-35394 UPD | 6.3 | 8.3 | 0.0045 | 2026-04-06 |
CVE-2026-53407 UPD | 6.1 | 8.1 | 0.0041 | 2026-06-12 |
CVE-2026-53408 | 6.1 | 8.1 | 0.0036 | 2026-06-12 |
CVE-2026-33335 | 6.0 | 8.0 | 0.0037 | 2026-03-24 |
CVE-2026-53418 | 6.0 | 8.1 | 0.0024 | 2026-10-13 |
CVE-2021-31384 UPD | 5.6 | 7.2 | 0.0116 | 2021-10-19 |
CVE-2026-1046 UPD | 5.4 | 7.6 | 0.0026 | 2026-02-16 |
CVE-2026-3471 UPD | 5.0 | 6.5 | 0.0033 | 2026-05-18 |
CVE-2020-11000 UPD | 4.8 | 5.7 | 0.0124 | 2020-04-08 |
CVE-2022-20736 UPD | 4.7 | 5.3 | 0.0106 | 2022-06-15 |
CVE-2023-43582 UPD | 4.6 | 5.5 | 0.0066 | 2023-11-15 |
CVE-2024-41918 | 4.5 | 6.1 | 0.0032 | 2024-08-29 |
CVE-2026-26123 | 4.5 | 5.5 | 0.0056 | 2026-03-10 |
CVE-2026-96614 | 4.2 | 5.4 | 0.0019 | 2026-10-15 |
CVE-2026-73335 | 4.0 | 5.3 | 0.0014 | 2026-08-26 |
CVE-2026-12189 UPD | 3.9 | 5.3 | 0.0010 | 2026-06-14 |
CVE-2026-12190 UPD | 3.9 | 5.3 | 0.0010 | 2026-06-14 |
CVE-2026-59717 UPD | 3.7 | 4.3 | 0.0038 | 2026-08-07 |
CVE-2024-35298 UPD | 3.6 | 4.3 | 0.0029 | 2024-06-19 |
CVE-2024-45203 UPD | 3.6 | 4.3 | 0.0029 | 2024-09-09 |
CVE-2025-5020 UPD | 3.6 | 4.3 | 0.0023 | 2025-05-21 |
CVE-2025-41408 UPD | 3.6 | 4.3 | 0.0027 | 2025-09-05 |
CVE-2024-54014 UPD | 2.9 | 3.6 | 0.0021 | 2024-12-05 |
CVE-2024-54125 UPD | 2.8 | 3.3 | 0.0017 | 2024-12-17 |