CyberSecBulletin
CVE-2025-48769NVD status: Analyzed

Apache NuttX RTOS: Use After Free

CVE-2025-48769 is a high-severity use after free vulnerability in Apache NuttX RTOS from Apache, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 12.11.0 as the first without the flaw, so updating Apache NuttX RTOS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.57% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache NuttX RTOS to 12.11.0 or a later version.
  2. Update Nuttx to 12.11.0 or a later version.
  3. Read the advisory on lists.apache.org for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache NuttX RTOS7.20 up to, but not including, 12.11.012.11.0
ApacheNuttx7.20 up to, but not including, 12.11.012.11.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.1HighNVD
CVSS 3.15.3MediumCISA (ADP)

Official description

Use After Free vulnerability was discovered in fs/vfs/fs_rename code of the Apache NuttX RTOS, that due recursive implementation and single buffer use by two different pointer variables allowed arbitrary user provided size buffer reallocation and write to the previously freed heap chunk, that in specific cases could cause unintended virtual filesystem rename/move operation results. This issue affects Apache NuttX RTOS: from 7.20 before 12.11.0. Users of virtual filesystem based services with write access especially when exposed over the network (i.e. FTP) are affected and recommended to upgrade to version 12.11.0 that fixes the issue.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Third-party and government advisories

Other vulnerabilities in Apache NuttX RTOS

All Apache NuttX RTOS vulnerabilities

Recent Use After Free vulnerabilities

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