NULL Pointer Dereference vulnerability in Apache Nimble. Missing validation of HCI connection complete or HCI command TX buffer could lead to NULL pointer dereference. This issue requires disabled asserts and broken or bogus Bluetooth controller and thus severity is considered low. This issue affects Apache NimBLE: through 1.8.0. Users are recommended to upgrade to version 1.9.0, which fixes the issue.
Conclusion & alert: CVE-2025-53477 is rated Moderate Risk (52.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.46%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-12 | 0.36% | 0.46% | +0.10% |
| 2 | 2026-03-19 | 0.35% | 0.36% | +0.01% |
| 3 | 2026-03-04 | — | 0.35% | — |
Full EPSS history (7 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| URL | Tags |
|---|---|
| https://github.com/apache/mynewt-nimble/commit/0caf9baeb271ede85fcc5237ab87ddbf938600da | Patch |
| https://github.com/apache/mynewt-nimble/commit/3160b8c4c7ff8db4e0f9badcdf7df684b151e077 | Patch |
| https://lists.apache.org/thread/1dxthc132hwm2tzvjblrtnschcsbw2vo | Mailing List Vendor Advisory |
| http://www.openwall.com/lists/oss-security/2026/01/08/3 | Mailing List Third Party Advisory |