CVE-2026-10648
NULL-pointer dereference in MCUmgr serial/console SMP transport on buffer-pool exhaustion
Description
mcumgr_serial_process_frag() in subsys/mgmt/mcumgr/transport/src/serial_util.c calls net_buf_reset() on the result of smp_packet_alloc() before checking it for NULL. smp_packet_alloc() uses net_buf_alloc(K_NO_WAIT) against the shared MCUmgr packet pool (CONFIG_MCUMGR_TRANSPORT_NETBUF_COUNT, default 4), which returns NULL when the pool is exhausted. In default builds the __ASSERT_NO_MSG in net_buf_reset is a no-op, so net_buf_simple_reset writes through the NULL pointer (buf->len = 0; buf->data = buf->__buf), causing a fault/crash. The fragment data reaches this code from attacker-controlled bytes on the MCUmgr serial/UART/shell-console transports (smp_uart.c, smp_raw_uart.c, smp_shell.c), and a fresh buffer is allocated at the start of essentially every new packet. An attacker on the serial/console link can flood the transport to drive the 4-entry buffer pool to exhaustion and induce the NULL dereference, crashing the device (denial of service). The defect was introduced after the original MCUmgr rework and shipped in Zephyr v4.4.0. The fix moves the NULL check ahead of net_buf_reset.
INFO
Published Date :
June 29, 2026, 11:16 p.m.
Last Modified :
July 14, 2026, 7:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-10648
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | e2e69745-5e70-4e92-8431-deb5529a81ad | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update to a patched version of the affected software.
- Ensure packet buffers are properly checked for NULL.
- Monitor packet buffer pool usage.
- Avoid flooding the transport with packets.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-10648.
| URL | Resource |
|---|---|
| https://github.com/zephyrproject-rtos/zephyr/commit/6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59 | Patch |
| https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j64f-h3ww-f32c | Exploit Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-10648 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-10648
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-10648 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-10648 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Jul. 14, 2026
Action Type Old Value New Value Changed Affected [{'vendor': 'zephyrproject', 'product': 'zephyr', 'versions': [{'status': 'affected', 'version': '4.4.0', 'lessThan': '4.5.0', 'versionType': 'semver'}], 'packageName': 'zephyr', 'collectionURL': 'https://github.com/zephyrproject-rtos/zephyr', 'defaultStatus': 'unaffected'}] [{'vendor': 'zephyrproject', 'product': 'zephyr', 'versions': [{'status': 'affected', 'version': '4.4.0', 'lessThan': '4.5.0', 'versionType': 'semver'}], 'packageName': 'zephyr', 'programFiles': ['subsys/mgmt/mcumgr/transport/src/serial_util.c'], 'collectionURL': 'https://github.com/zephyrproject-rtos/zephyr', 'defaultStatus': 'unaffected'}] Changed Description mcumgr_serial_process_frag() in subsys/mgmt/mcumgr/transport/src/serial_util.c calls net_buf_reset() on the result of smp_packet_alloc() before checking it for NULL. smp_packet_alloc() uses net_buf_alloc(K_NO_WAIT) against the shared MCUmgr packet pool (CONFIG_MCUMGR_TRANSPORT_NETBUF_COUNT, default 4), which returns NULL when the pool is exhausted. In default builds the __ASSERT_NO_MSG in net_buf_reset is a no-op, so net_buf_simple_reset writes through the NULL pointer (buf->len = 0; buf->data = buf->__buf), causing a fault/crash. The fragment data reaches this code from attacker-controlled bytes on the MCUmgr serial/UART/shell-console transports (smp_uart.c, smp_raw_uart.c, smp_shell.c), and a fresh buffer is allocated at the start of essentially every new packet. An attacker on the serial/console link can flood the transport to drive the 4-entry buffer pool to exhaustion and induce the NULL dereference, crashing the device (denial of service). The defect was introduced after the original MCUmgr rework and shipped in Zephyr v4.4.0. The fix moves the NULL check ahead of net_buf_reset. mcumgr_serial_process_frag() in subsys/mgmt/mcumgr/transport/src/serial_util.c calls net_buf_reset() on the result of smp_packet_alloc() before checking it for NULL. smp_packet_alloc() uses net_buf_alloc(K_NO_WAIT) against the shared MCUmgr packet pool (CONFIG_MCUMGR_TRANSPORT_NETBUF_COUNT, default 4), which returns NULL when the pool is exhausted. In default builds the __ASSERT_NO_MSG in net_buf_reset is a no-op, so net_buf_simple_reset writes through the NULL pointer (buf->len = 0; buf->data = buf->__buf), causing a fault/crash. The fragment data reaches this code from attacker-controlled bytes on the MCUmgr serial/UART/shell-console transports (smp_uart.c, smp_raw_uart.c, smp_shell.c), and a fresh buffer is allocated at the start of essentially every new packet. An attacker on the serial/console link can flood the transport to drive the 4-entry buffer pool to exhaustion and induce the NULL dereference, crashing the device (denial of service). The defect was introduced after the original MCUmgr rework and shipped in Zephyr v4.4.0. The fix moves the NULL check ahead of net_buf_reset. -
Initial Analysis by [email protected]
Jul. 01, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:o:zephyrproject:zephyr:4.4.0:-:*:*:*:*:*:* *cpe:2.3:o:zephyrproject:zephyr:4.4.0:rc1:*:*:*:*:*:* *cpe:2.3:o:zephyrproject:zephyr:4.4.0:rc2:*:*:*:*:*:* *cpe:2.3:o:zephyrproject:zephyr:4.4.0:rc3:*:*:*:*:*:* Added Reference Type Zephyr Project: https://github.com/zephyrproject-rtos/zephyr/commit/6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59 Types: Patch Added Reference Type Zephyr Project: https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j64f-h3ww-f32c Types: Exploit, Patch, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 30, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-10648', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-30T13:12:36.467942Z'} -
New CVE Received by [email protected]
Jun. 29, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'zephyrproject', 'product': 'zephyr', 'versions': [{'status': 'affected', 'version': '4.4.0', 'lessThan': '4.5.0', 'versionType': 'semver'}], 'packageName': 'zephyr', 'collectionURL': 'https://github.com/zephyrproject-rtos/zephyr', 'defaultStatus': 'unaffected'}] Added Description mcumgr_serial_process_frag() in subsys/mgmt/mcumgr/transport/src/serial_util.c calls net_buf_reset() on the result of smp_packet_alloc() before checking it for NULL. smp_packet_alloc() uses net_buf_alloc(K_NO_WAIT) against the shared MCUmgr packet pool (CONFIG_MCUMGR_TRANSPORT_NETBUF_COUNT, default 4), which returns NULL when the pool is exhausted. In default builds the __ASSERT_NO_MSG in net_buf_reset is a no-op, so net_buf_simple_reset writes through the NULL pointer (buf->len = 0; buf->data = buf->__buf), causing a fault/crash. The fragment data reaches this code from attacker-controlled bytes on the MCUmgr serial/UART/shell-console transports (smp_uart.c, smp_raw_uart.c, smp_shell.c), and a fresh buffer is allocated at the start of essentially every new packet. An attacker on the serial/console link can flood the transport to drive the 4-entry buffer pool to exhaustion and induce the NULL dereference, crashing the device (denial of service). The defect was introduced after the original MCUmgr rework and shipped in Zephyr v4.4.0. The fix moves the NULL check ahead of net_buf_reset. Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-476 Added Reference https://github.com/zephyrproject-rtos/zephyr/commit/6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59 Added Reference https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-j64f-h3ww-f32c